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Wednesday 30 September 2015

How to Spot a Liar

Forget body language or eye movements. There are much better ways to identify the deceitful.

(Credit: Getty Images)


Thomas Ormerod’s team of security officers faced a seemingly impossible task. At airports across Europe, they were asked to interview passengers on their history and travel plans. Ormerod had planted a handful of people arriving at security with a false history, and a made-up future – and his team had to guess who they were. In fact, just one in 1000 of the people they interviewed would be deceiving them. Identifying the liar should have been about as easy as finding a needle in a haystack.
Using previous methods of lie detection, you might as well just flip a coin
So, what did they do? One option would be to focus on body language or eye movements, right? It would have been a bad idea. Study after study has found that attempts – even by trained police officers – to read lies from body language and facial expressions are more often little better than chance. According to one study, just 50 out of 20,000 people managed to make a correct judgement with more than 80% accuracy. Most people might as well just flip a coin.
Ormerod’s team tried something different – and managed to identify the fake passengers in the vast majority of cases. Their secret? To throw away many of the accepted cues to deception and start anew with some startlingly straightforward techniques.
Over the last few years, deception research has been plagued by disappointing results. Most previous work had focused on reading a liar’s intentions via their body language or from their face – blushing cheeks, a nervous laugh, darting eyes. The most famous example is Bill Clinton touching his nose when he denied his affair with Monica Lewinsky – taken at the time to be a sure sign he was lying. The idea, says Timothy Levine at the University of Alabama in Birmingham, was that the act of lying provokes some strong emotions – nerves, guilt, perhaps even exhilaration at the challenge – that are difficult to contain. Even if we think we have a poker face, we might still give away tiny flickers of movement known as “micro-expressions” that might give the game away, they claimed.
The problem is the huge variety of human behaviour – there is no universal dictionary of body language
Yet the more psychologists looked, the more elusive any reliable cues appeared to be. The problem is the huge variety of human behaviour. With familiarity, you might be able to spot someone’s tics whenever they are telling the truth, but others will probably act very differently; there is no universal dictionary of body language. “There are no consistent signs that always arise alongside deception,” says Ormerod, who is based at the University of Sussex. “I giggle nervously, others become more serious, some make eye contact, some avoid it.” Levine agrees: “The evidence is pretty clear that there aren’t any reliable cues that distinguish truth and lies,” he says. And although you may hear that our subconscious can spot these signs even if they seem to escape our awareness, this too seems to have been disproved.
Despite these damning results, our safety often still hinges on the existence of these mythical cues. Consider the screening some passengers might face before a long-haul flight – a process Ormerod was asked to investigate in the run up to the 2012 Olympics. Typically, he says, officers will use a “yes/no” questionnaire about the flyer’s intentions, and they are trained to observe “suspicious signs” (such as nervous body language) that might betray deception. “It doesn’t give a chance to listen to what they say, and think about credibility, observe behaviour change – they are the critical aspects of deception detection,” he says. The existing protocols are also prone to bias, he says – officers were more likely to find suspicious signs in certain ethnic groups, for instance. “The current method actually prevents deception detection,” he says.
Clearly, a new method is needed. But given some of the dismal results from the lab, what should it be? Ormerod’s answer was disarmingly simple: shift the focus away from the subtle mannerisms to the words people are actually saying, gently probing the right pressure points to make the liar’s front crumble.
Ormerod and his colleague Coral Dando at the University of Wolverhampton identified a series of conversational principles that should increase your chances of uncovering deceit:
Use open questions. This forces the liar to expand on their tale until they become entrapped in their own web of deceit.
Employ the element of surprise. Investigators should try to increase the liar’s “cognitive load” – such as by asking them unanticipated questions that might be slightly confusing, or asking them to report an event backwards in time – techniques that make it harder for them to maintain their façade.
Watch for small, verifiable details. If a passenger says they are at the University of Oxford, ask them to tell you about their journey to work. If you do find a contradiction, though, don’t give yourself away – it’s better to allow the liar’s confidence to build as they rattle off more falsehoods, rather than correcting them.
Observe changes in confidence. Watch carefully to see how a potential liar’s style changes when they are challenged: a liar may be just as verbose when they feel in charge of a conversation, but their comfort zone is limited and they may clam up if they feel like they are losing control.
Liar vs liar
It takes one to know one
Ironically, liars turn out to be better lie detectors. Geoffrey Bird at University College London and colleagues recently set up a game in which subjects had to reveal true or false statements about themselves. They were also asked to judge each other’s credibility. It turned out that people who were better at telling fibs could also detect others’ tall tales, perhaps because they recognised the tricks.
The aim is a casual conversation rather than an intense interrogation. Under this gentle pressure, however, the liar will give themselves away by contradicting their own story, or by becoming obviously evasive or erratic in their responses. “The important thing is that there is no magic silver bullet; we are taking the best things and putting them together for a cognitive approach,” says Ormerod.
Ormerod openly admits his strategy might sound like common sense. “A friend said that you are trying to patent the art of conversation,” he says. But the results speak for themselves. The team prepared a handful of fake passengers, with realistic tickets and travel documents. They were given a week to prepare their story, and were then asked to line up with other, genuine passengers at airports across Europe. Officers trained in Ormerod and Dando’s interviewing technique were more than 20 times more likely to detect these fake passengers than people using the suspicious signs, finding them 70% of the time.
“It’s really impressive,” says Levine, who was not involved in this study. He thinks it is particularly important that they conducted the experiment in real airports. “It’s the most realistic study around.”
The art of persuasion
Levine’s own experiments have proven similarly powerful. Like Ormerod, he believes that clever interviews designed to reveal holes in a liar’s story are far better than trying to identify tell-tale signs in body language. He recently set up a trivia game, in which undergraduates played in pairs for a cash prize of $5 for each correct answer they gave. Unknown to the students, their partners were actors, and when the game master temporarily left the room, the actor would suggest that they quickly peek at the answers to cheat on the game. A handful of the students took him up on the offer.
One expert was even correct 100% of the time, across 33 interviews
Afterwards, the students were all questioned by real federal agents about whether or not they had cheated. Using tactical questions to probe their stories – without focusing on body language or other cues – they managed to find the cheaters with more than 90% accuracy; one expert was even correct 100% of the time, across 33 interviews – a staggering result that towers above the accuracy of body language analyses. Importantly, a follow-up study found that even novices managed to achieve nearly 80% accuracy, simply by using the right, open-ended questions that asked, for instance, how their partner would tell the story.
Indeed, often the investigators persuaded the cheaters to openly admit their misdeed. “The experts were fabulously good at this,” says Levine. Their secret was a simple trick known to masters in the art of persuasion: they would open the conversation by asking the students how honest they were. Simply getting them to say they told the truth primed them to be more candid later. “People want to think of being honest, and this ties them into being cooperative,” says Levine. “Even the people who weren’t honest had difficulty pretending to be cooperative [after this], so for the most part you could see who was faking it.”
Another trick is to ask people how honest they are
Clearly, such tricks may already be used by some expert detectives – but given the folklore surrounding body language, it’s worth emphasising just how powerful persuasion can be compared to the dubious science of body language. Despite their successes, Ormerod and Levine are both keen that others attempt to replicate and expand on their findings, to make sure that they stand up in different situations. “We should watch out for big sweeping claims,” says Levine.
Although the techniques will primarily help law enforcement, the same principles might just help you hunt out the liars in your own life. “I do it with kids all the time,” Ormerod says. The main thing to remember is to keep an open mind and not to jump to early conclusions: just because someone looks nervous, or struggles to remember a crucial detail, does not mean they are guilty. Instead, you should be looking for more general inconsistencies.
There is no fool-proof form of lie detection, but using a little tact, intelligence, and persuasion, you can hope that eventually, the truth will out.


http://www.bbc.com/future/story/20150906-the-best-and-worst-ways-to-spot-a-liar

This post is on Healthwise

Monday 28 September 2015

The Truth about Pigs

They have a reputation as filthy animals, sweating profusely while wallowing in mud. In fact they have a superpower

A domestic pig enjoys a good wallow in mud (Credit: Lynn M. Stone/NPL)

Reputation: Pigs sleep and root in faeces. Pigs sweat like pigs. Pigs are filthy animals. Pigs are pink. Male pigs can orgasm for half an hour.
Reality: These stereotypes are best explained by poor husbandry. In the wild, boars don't sleep and root in poo, they eat plants. They do wallow in mud but only because it's a good way to keep cool. Domesticated pigs are often pink, but only because we made them that way. Male pigs can ejaculate for minutes at a time.
"I don't eat nothin' that ain't got sense enough to disregard its own faeces." So says Jules Winnfield, the hitman played by Samuel L. Jackson in Pulp Fiction, explaining why he doesn't eat pork.
A group of wild boars at Basel Zoo in Switzerland has become famous for its food hygiene
Had Winnfield taken a moment to think, he might not have been so snarky about pigs. Rabbits happily snaffle their own faecal pellets, to give the relatively indigestible grasses a second passage through their digestive system, but nobody is rude about bunnies.
Wild boars – the ancestral stock from which we have fashioned our domesticated pigs – are omnivores, and not too fussy about what they eat. Yet 90% of their diet is made up of plant matter, so they probably don't have a particular taste for poo.
If a domestic pig occasionally munches on the odd turd, it's most likely because its cramped home makes it hard not to. In fact, a group of wild boars at Basel Zoo in Switzerland has become famous for its food hygiene.
Boars will wallow in mud, but they probably do it to keep cool
The animals were given apple slices coated in sand. Rather than eating them immediately, they carried them "to the edge of a creek running through their enclosure where they put the fruits in the water and pushed them to and fro with their snouts before eating."
The boars would never do this for clean apples. Even if they were really hungry, they still took the time to wash their food.
Aside from their food choices, pigs also have a reputation for being more generally filthy.
Boars will wallow in mud, but they probably do it to keep cool.
Rubbing off a layer of caked mud may also be a nifty way to remove ticks and other parasites
This is because pigs do not have functional sweat glands, which is worth remembering next time someone claims they are "sweating like a pig". This physiological reality means that pigs are at serious risk of overheating, and muddy water evaporates much more slowly than clean water.
A layer of mud on the skin may serve other purposes too, acting like sun cream to prevent the skin from burning, or as an insect repellent to deter mosquitoes and the like. Rubbing off a layer of caked mud may also be a nifty way to remove ticks and other parasites."A pig, like any animal, is going to try to be comfortable," says Greger Larson of the University of Oxford in the UK. "If that means getting dirty to stay cool then that's what it's going to do. It would probably find other solutions but those haven't been provided because you're keeping them in relatively dense pens."
Paradoxically then, wallowing in mud may make for clean rather than dirty skin. It is also worth remembering that the pink, almost hair-free animal that comes to mind at the mention of the word "pig" is a relatively recent human innovation.
Humans have cherry-picked rare mutations that would be quickly eliminated in wild contexts
Domestic pigs, and their wild relatives the wild boars, are just one member of an entire family of piggy animals called the Suidae. The family includes over a dozen species, from warthogs to pygmy hogsbabirusasgiant forest hogs and African bushpigs.
Genetic evidence suggests that wild boars were domesticated twice, from lineages in Asia and Europe. These ancestral boars began to diverge around one million years ago – long before domestication, which happened around 9,000 years ago. Despite this long separation, Asian and European wild boars have exactly the same camouflaged appearance.
The same cannot be said for domestic breeds. In these pigs, the gene encoding coat colour is immensely variable, and accordingly they display a range of colours and patterns.
We have fashioned this diversity in less than 10,000 years, says Larson. In a paper published in 2009, he and his colleagues wrote that "humans have cherry-picked rare mutations that would be quickly eliminated in wild contexts."
There is one final rumour that has to be addressed: the oft-repeated "fact" that male pigs can orgasm for 30 minutes.
According to observations of males with real sows, copulation duration is typically 4-5 minutes, but can last up to 20 minutes
The first thing to say is that we don't know what sensations the males – or the females for that matter – experience when they mate, so any talk of orgasms is speculative.
But based on the ubiquitous "gloved hand" method used to coax sperm from male pigs, ejaculation does appear to last a very long time. In a 2012 study of "high performance boars", the average duration of ejaculation was around 6 minutes. But there was considerable variation, with one male apparently yielding semen continuously for 31 minutes.
It is difficult to know whether this kind of protracted ejaculation can occur in the absence of the "gloved hand", but it is certainly a possibility. According to observations of males with real sows, copulation duration is typically 4-5 minutes, but can last up to 20 minutes.
Whatever the truth about orgasms, an online primer on how to artificially inseminate pigs warns practitioners not to interrupt the male before he's done, unless they want a very angry pig on their hands. "If you let loose too soon, be prepared for a challenge."

http://www.bbc.com/earth/story/20150924-the-truth-about-pigs

This post is on Healthwise

Friday 25 September 2015

Can eating more than six bananas at once kill you?



It's sometimes said that eating a lot of bananas at once could be dangerous - it has even been suggested that eating more than six in one sitting could kill you. Can this really be true?


    13 September 2015

Bunch of seven bananas
Bananas are one of the world's most popular fruits, stuffed with vitamins and minerals. On the face of it they are good for you, so why do some people think they could be fatal?
One well-known figure who has spread this idea around is Karl Pilkington, the grumpy friend of comedian Ricky Gervais.
"Before when you were talking about bananas... I had that fact, about if you eat more than six, it can kill you," he said in one of his conversations with Gervais and fellow comedian Stephen Merchant.
"It is a fact. Potassium levels are dangerously high if you have six bananas... I saw a bowl of bananas. There's six bananas there. You know why there's only six? Seven would be dangerous."
So how dangerous is potassium? Actually, it is crucial for survival and can be found "within every single cell of the body," says Catherine Collins, a dietitian at St George's Hospital in London.
"We use it to help generate an electrical charge which helps the cell function properly. It helps keep your heart rate steady, it helps trigger insulin release from the pancreas to help control blood sugars, and more importantly keeps blood pressure in check."
On the other hand, if the level of potassium in the body is too low or too high it can result in an irregular heartbeat, stomach pain, nausea and diarrhoea. Potassium chloride is even one of the chemicals used in lethal injections in the US, as extremely high doses can cause cardiac arrest.
But for a healthy person, "it would be impossible to overdose on bananas," says Collins. "You would probably need around 400 bananas a day to build up the kind of potassium levels that would cause your heart to stop beating... Bananas are not dangerous - and in fact they are, and always have been, very good for you."
Adults should consume about 3,500mg of potassium per day, according to the UK's National Health Service. The average banana, weighing 125g, contains 450mg of potassium, meaning a healthy person can consume at least seven-and-half bananas before reaching the recommended level.
There are some people who should steer clear of foods that are high in potassium though, warns Collins - those with kidney disease.
"These patients have a very low kidney function which can potentially see a build-up of harmful potassium levels in their blood stream because they can't get rid of the mineral when they pass urine," she says. "So in theory it is possible for someone with kidney disease to die of a high blood potassium level if they decided to consume lots of different food types rich in the mineral."
She once had a patient on dialysis who had a heart attack after eating too many tomatoes - another fruit rich in potassium. His kidneys had already stopped working so he was unable to get rid of the excess.
Another thing that could cause some to worry about bananas is radiation.
Like many foods, bananas naturally contain some radioactive isotopes - enough for the US-based think tank, Nuclear Threat Initiative, to warn that they can trigger sensors used at US ports to detect smuggled nuclear material.
A typical banana contains 0.1 microsieverts of radiation. To put that in context, a typical CT scan in a hospital exposes humans to between 10 and 15 millisieverts - about 100,000 times more.
"The levels of radioactivity are negligible," says Collins. "Bananas are not as radioactive as Brazil nuts and they are safe to eat in moderation."

This post is on Healthwise

Saturday 19 September 2015

Immune System Strengthening

Age, stress, and poor nutrition can sap our immune system of its effectiveness. Influenza provides one example; during young adulthood, when the body can mount a robust immune response to this common virus, influenza is rarely fatal. Among the elderly, however, the virus is associated with significant rates of death and hospitalization (Nichol 2005).

LIFE EXTENSION
HEALTH CONCERNS




The impact of aging on the immune system is profound. As people age, a number of critical immune system components including cellular response, antibody production, and response to vaccines are reduced or slowed. At the same time, susceptibility to infection and cancer is increased. Some of this increased susceptibility to disease is linked to chronic inflammation, which is associated with many disorders of aging (Ershler 2000; Hamerman 1999; Taaffe 2000).
Age, however, is not the sole culprit in reduced immune function. There is no question that exercise, stress, and nutritional status play an important role in maintaining a healthy immune system. Consider the following research findings:
  • Dietary deficiencies and malabsorption alter metabolism and exacerbate chronic disorders (Kaput 2004). An imbalance in the intake of dietary fat, carbohydrate, and protein can contribute to the development of disease(s) (Kaput 2004). On the other hand, there is overwhelming evidence of the benefits of a good diet on reducing the risk of many chronic diseases (Ames 2001; Kaput 2004).
  • Malnutrition causes a decline in immune function and increases susceptibility to infection (Brussow 1995; Lotfy 1998; delaFuente 1998). Likewise, a vitamin or mineral deficiency can suppress immune system function (delaFuente 1998). Correct choices of supplements, vitamins, minerals, fatty acids, probiotics, and botanicals have been shown to boost immunity and may also reduce the risk of disease(s) in healthy Individuals (Kaminogawa 2004).
  • Psychological health influences the immune system and the course of many diseases (Kiecolt-Glaser 2000). Depression, stress, and anxiety increase the production of pro-inflammatory chemicals in the blood, which in turn can compromise, depress, or suppress the immune system (Appels 2000; Dentino 1999; Maes 1997; Maes 1998; Maes 1999; Boscarino 1999; Lutgendorf 1999; Zhou 1993; Papanicolaou 1998).
  • High levels of anxiety are associated with decreased immune function (Ironson 1990; Koh 1998; Boscarino 1999; Kiecolt-Glaser 2000).
  • Chronic stress can provoke long-term increases in pro-inflammatory chemicals. For example, caregiving for a relative with a serious medical condition results in long-term immune suppression among women (Lutgendorf 1999).
  • Chronic stress from persistent marital problems, burnout at work (Lerman 1999), and lengthy unemployment (Arnetz 1991) can lead to immune alterations that persist for years (Boscarino 1999; Kiecolt-Glaser 1987; Kiecolt-Glaser 1997; Kiecolt-Glaser 1988; Kiecolt-Glaser 1993).
Life Extension believes that all aging people should take action to bolster their immune systems. This includes reducing negative psychological stress; following a physician-approved, moderate, long-term exercise program; and following a diet as well as consuming nutrients that have been shown to enhance immune response and promote health.

The Immune System: How it Works

The immune system is an elegant and complex set of components that combine to fight disease, infection(s), and various pathogens. A healthy immune system distinguishes organisms in the body as “self” or “non-self.” An intact immune response identifies pathogens as “non-self” and rapidly destroys them. A depressed immune system, by contrast, will allow invading organisms to flourish.
When the immune system mistakenly recognizes a “self” cell as “non-self” and mounts an immune response, it can result in an autoimmune disorder (eg, rheumatoid arthritis).
In general, the body has two primary defense mechanisms: natural immunity and acquired immunity. Natural immunity is the “first responder” to attack. Natural immune response relies on various white blood cells and physical barriers to block or immediately attack any foreign invader and attempt to destroy it.
Acquired immunity, on the other hand, involves antibodies created in response to specific foreign antigens. This sort of response requires a few days for the body to recognize the invader and manufacture antibodies against it. Once the body has manufactured a particular antibody for a specific invader, the immune system response is faster and more effective the next time that invader appears (Janeway 1999; Beers 2004).
The natural immune system relies on a host of weapons to protect the body, including various kinds of white blood cells (see Table 1). These natural defenses include the following organs, chemicals, and processes:
Physical and chemical barriers. The body's first lines of defense are the skin and mucous membranes, which prevent the entrance of many pathogens. There are also many secondary barriers. For example, tears, sweat, and saliva combat some bacteria; also, the hydrochloric acid as well as protein-digesting enzymes secreted by the stomach are lethal to many, but not all pathogens (Janeway 1999; Beers 2004).
Inflammation and fever. Inflammation is a nonspecific response to infection or tissue injury. The four signs of inflammatory response are redness, swelling, heat, and pain. Inflammation begins when cells release certain cytokines, including interleukin (IL)-1, IL-6, and tumor necrosis factor-alpha (TNF-α) (Janeway 1999; Beers 2004).
Phagocytic cells. Phagocytic cells engulf and destroy foreign cells. Phagocytic cells are white blood cells and include neutrophils, eosinophils, and macrophages; they have short lives and must be continually replenished by the body. Neutrophils and macrophages are very important aspects of the innate defenses of the body (Janeway 1999; Beers 2004).
Natural killer cells. Natural killer cells destroy certain cancer cells and a variety of pathogens. Killer cells are active secretors of interferon, an important and potent protein. Natural killer cells attach directly to the surfaces of infected cells and cause them to burst. They can also kill a pathogen by making its outer membrane leak (Janeway 1999; Beers 2004).
Antimicrobial proteins. Infected immune cells produce interferon, which causes healthy cells to produce antiviral proteins. There are more than 30 distinct antiviral proteins. When an individual complement (immune system) protein is activated by infecting organisms, it triggers a cascade that activates other complement proteins. Activated proteins can destroy bacteria while sparing host cells or cause the infected cells to become engulfed by phagocytic cells (Janeway 1999; Beers 2004).
Cytokines. Cells use chemical messengers (ie, cytokines) to communicate and share information; each chemical sends a different message to other cells. Cytokines regulate immunity, inflammation, and the production of white blood cells. There are dozens of cytokines; each performs a specific set of activities against specific target cells. They can act in concert or in opposition. Cytokines are often produced in a cascade; in other words, a cytokine stimulates its target cells to make additional cytokines. TNF-α, IL-1, IL-6, and type I interferon are important cytokines in the regulation of natural immunity.
Acute-phase proteins. Acute-phase response is activated during critical illness. When phagocytic cells bind pathogens, they release pro-inflammatory cytokines. This response enables the body to recognize invaders before immune responses have been fully activated. Acute-phase proteins promote inflammation and stimulate phagocytes to move where they are needed.
Table 1. Major Cells of the Immune System (Janeway 1999; Nairm 2000)
Cell
Activity
Lymphocytes
Natural killer cells
Destroy a variety of tumor cells and antibody-coated target cells; not antigen specific.
Cytotoxic T (CD8+) cells
Secrete cytokines that attract macrophages and increase their phagocytic activity; destroy target cells that display the same antigen that activated their progenitor cell; lyse infected cells by releasing toxins. Cytotoxic T cells fight foreign invaders by destroying cells that display the antigen that activated its progenitor cells (immunological surveillance).
Helper T (T4+) cells
Stimulate cellular immunity and inflammation; secrete cytokines that stimulate proliferation of B cells and other T cells; amplify antibody production by plasma cells.
Suppressor T cells
Suppress activity of naïve (un-stimulated) and effector T cells.
Memory T cells
Recognize antigens that have invaded in the past, which allows for a larger and more rapid response when there is a second encounter with that antigen.
B lymphocytes (B cells)
Differentiate into antibody-producing plasma cells; process and present antigen to helper T cells; display immunoglobulin and class II MHC antigens.
Plasma cells
Main antibody-secreting cells.
Memory B cells
Descendants of B cells that remain after an immune response.
Phagocytes
Macrophages
Phagocytize antigens, then process and present them to T cells for destruction; attack dead and defective blood cells; secrete cytokines that induce proliferation of B and T cells.
Neutrophils
Major defense against bacteria; first on scene to fight infection.
Eosinophils
Active against parasites and commonly elevated in allergies.
Dendritic cells (interdigitating reticular cells)
Process and present antigens to T and B cells; most potent stimulators of T cell responses.
Antigen-presenting cells
Engulf antigens, process them internally, and then display fragments of them on their surface; surface markers alert other immune cells that there is an invader. Identified antigen-presenting cells: dendritic cells, macrophages, and B lymphocytes.

Inflammation, Free Radicals, and Cytokines

Although acute inflammation is an important immune system response, chronic inflammation has also been linked to many diseases, including heart disease. Besides being associated with pro-inflammatory cytokines, inflammation may be related to the overproduction of free radicals (Janeway 1999).
A free radical is an atom or group of atoms (ie, a molecule) with unpaired electrons. Free radicals are extremely unstable and react easily with other molecules, thereby changing their chemical composition. Oxygen is especially susceptible to free radical formation. Free radicals derived from oxygen are known as reactive oxygen species (ROS), or oxidants.
When the body has increased levels of ROS (ie, when it is experiencing oxidative stress), widespread damage may result. At high concentrations, free radicals can damage fats, proteins, and nucleic acids. They can also cause cell death, gene mutations, and cancer (Moslen 1994). Several diseases may be the result of cellular and genetic damage caused by free radicals, including several immune disorders (Moslen 1994).
In order to reduce the damage caused by elevated free radicals and cytokines (both part of the natural immune system), the body fights back by producing antioxidants and hormones (eg, cortisol) to suppress the immune system (Grimble 1996). Antioxidants are valuable because they pair with unstable free radicals, thereby limiting the damage free radicals can inflict on other cells.

What You Have Learned So Far...

  • The immune system declines as we age, making us more susceptible to various diseases and pathogens.
  • Immune system health is closely related to stress, frequency of exercise, and nutritional status. Poor intake of vital nutrients is closely associated with depressed immune response and increased rate of disease.
  • The immune system has two primary defense mechanisms: natural, which uses white blood cells and physical barriers to protect against disease, and acquired, in which specialized cells generate antibodies to defend against specific pathogens.
  • Inflammation is caused by multiple factors, including microorganisms, physical stress, tissue death, and inappropriate immune response. Chronic inflammation is linked to diseases such as heart disease. Inflammation is mediated by cytokines and free radicals. It is an important immune system response, but can also be dangerous because a chronic inflammatory state is linked to various diseases of aging.
  • Free radicals are unstable molecules that readily react with other molecules, especially oxygen, to change their chemical composition. Antioxidants are used by the body to scavenge for free radicals and limit the amount of damage they can cause.

Nutrition, Immunity, and Your Genes


Researchers are just now beginning to understand how genes affect nutrition and overall immunity. It turns out that the overall risk of contracting many diseases is influenced by genetics (Mathew 2001). A new field of nutritional genomics explores the interaction of nutrition, genes, and environmental factors (including diet) (Kaput 2004).
This emerging field of science evolved from the Human Genome Project, which mapped the human genome and identified many genes that cause disease.
The association between diet and chronic diseases such as atherosclerosis, diabetes, obesity, and cancer is well known (Jenkins 1997; Jenkins 1999; Jenkins 2000; Kaput 2004). Nutrients supplied by food are an important variable in gene expression. Deficiency of some essential nutrients can alter metabolism and the structure of DNA (Kaput 2004). A well-studied example of the relationship between genetics and diet is type 2 diabetes. This condition is associated with a sedentary lifestyle, being overweight, and ethnicity. Although some individuals are genetically predisposed to this condition, many can control symptoms through exercise and a change in diet (Kaput 2004).
In the future, genetic testing might be able to help in the creation of nutritional programs tailored to each individual's genetic makeup; thus, may help people fight disease and stay healthy.

Supporting a Healthy Immune System


A healthy immune system grows ever more important as we age, and immune status is closely associated with nutrition, exercise, and stress reduction. Older people and people with compromised immune systems should talk to their physician about exercising, reducing stress, and designing an active, immune-boosting nutritional program.
Vitamin D. Adults (and children) with higher vitamin D levels contract substantially fewer cold, flu, and other viral infections (Ginde 2009; Karatekin 2007; Cannell 2006). Vitamin D downregulates the expression of pro-inflammatory cytokines while upregulating the expression of antimicrobial peptides in immune cells (Schauber 2007). This biological mechanism explains why Vitamin D confers such dramatic protection against common illnesses.
Glutathione boosters. Glutathione is probably the body's most important cellular defense against free radical damage. It is a free radical scavenger and major antioxidant.
Low levels of glutathione are linked to many diseases. Malnutrition and aging (Cai 2000) deplete glutathione. Glutathione is also involved in one of the major liver detoxification pathways.
Glutathione is produced in the body, but not easily absorbed when taken orally. Instead, glutathione precursors may be used by the body to increase glutathione (Bounous 2000). Glutathione precursors include glutamine, N-acetylcysteine (NAC), and S-adenosyl-L-methionine (SAMe) (Devlin 2002). It can also be upregulated by lipoic acid as well as vitamins C and E.
Glutamine. Glutamine is the most abundant amino acid in the body (Roth 2002). Glutamine depletion causes downregulation of glutathione levels in the body (Roth 2002), and dietary supplementation increases these levels (Roth 2002). Glutamine has immunoregulative activities (Roth 2002; Li 1995). Lymphocytes and macrophages use glutamine at a very high rate (Newsholme 1994). Glutamine stimulates lymphocyte production and killer immune cell activity (Rohde 1995, 1998, 1996; Jurectic 1994).
Glutamine depletion slows wound healing and increases the risk of organ failure under certain conditions (Wilmore 1991). Endurance athletes whose muscles do not fully recover between workouts have decreased glutamine levels (Shephard 1998; Castell 1998). Some scientists believe that intense physical exercise or stress due to trauma, burns, or sepsis (blood infection) forces the body into glutamine debt, which temporarily compromises immune function (Newsholme 1994).
S-adenosyl-L-methionine. S-adenosyl-L-methionine (SAMe) is a natural amino acid present throughout the body. It is crucially important because it is involved in dozens of chemical reactions, including the synthesis of DNA and RNA, proteins, melatonin, creatine, and many others. SAMe is an important energy source (Osman 1993) and intrinsically related to the synthesis of glutathione.
N-acetylcysteine. N-acetylcysteine (NAC) acts as an antioxidant and is recommended for conditions that increase oxidative stress or decrease glutathione levels (Burgunder 1989). NAC has a protective effect on DNA and is a powerful free radical scavenger. It increases the synthesis of glutathione only when there is a demand, and is thought to concentrate only in tissues where it is required (Burgunder 1989). NAC can modulate the concentrations of certain cytokines. In laboratory studies, it has increased IL-1 and IL-2 levels when they are at low concentrations and decreased these cytokines at higher concentrations (Baier 1996). It also demonstrated an ability to inhibit cell growth and proliferation in cancer cell lines (Chiao 2000), and prevent the transformation of carcinogens into more toxic compounds (De Flora 1984; Wilpart 1986).

Antioxidants and Coenzyme Q10

Because of their ability to scavenge free radicals, antioxidants are important immune-system boosters. Supplementation with antioxidants like vitamins C, E, and B vitamins may improve immune function (Grimble 1997), and supplementation with vitamin A stimulates antibody-mediated immune responses (Cantorna 1995).
Vitamin E is a powerful fat-soluble antioxidant. It protects cellular membranes of the immune system and other cells by trapping free radicals, and enhances the effectiveness of lymphocytes (Kaminogawa 2004).
Vitamin C (ascorbic acid) is a key component of the immune system and antioxidant defense (Kagan 1991, 1992; Peters 1993). It prevents the production of free radicals and reduces DNA damage in immune cells. Moreover, vitamin C downregulates the production of pro-inflammatory cytokines and participates in recycling vitamin E (Schwager 1998).
B vitamins indirectly contribute to antioxidant defenses and have considerable influence on immune function. Vitamins B12 and B6 are cofactors in the creation of cysteine, a key component in glutathione synthesis. Deficiencies in B vitamins and vitamin E create abnormalities in immune response (Murrary 2000).
Lipoic acid is a potent antioxidant with antiviral, free-radical-quenching, and immune-boosting qualities. It is unusual because it is soluble in both fat and water (Kagan 1992), and is active in both its oxidized and reduced forms (Bustamante 1998). Lipoic acid is able to regenerate other antioxidants (eg, vitamins C and E) and raise glutathione levels significantly (Packer 1995, 1997; Scholich 1989; Fuchs 1993).
Coenzyme Q10 (CoQ10), synthesized from the amino acid tyrosine, is present in high quantities in the heart muscle. CoQ10 has shown a wide range of benefits. It is an essential cofactor in the production of adenosine triphosphate (ATP), which is the primary source of energy for all the body's cells. Levels of CoQ10 decline naturally as humans age, which may be related to increased lipid peroxidation. CoQ10 is a powerful antioxidant and scavenger of free radicals. It inhibits lipid peroxidation and works synergistically with vitamin E (Alleva 1995). CoQ10 has an important role in the stimulation of the immune system and improves several parameters of immune function (Folkers 1985).
Whey protein. Whey protein is isolated from milk. Proteins in whey are highly available to the body, and whey protein contains potent antioxidants. Its antioxidant activity is due to its high concentrations of glutamate and cysteine, which are precursors to glutathione (Walzem 2002). Whey also contains several substances that enhance the immune system, including the following:
  • Beta-lactoglobulin, which modulates lymphatic responses (Guimont 1997)
  • Alpha-lactalbumin, which has a direct effect on B and T lymphocytes and has the ability to reduce oxidative stress
  • Lactoperoxidase, which reduces toxic hydrogen peroxide (Sundberg 1991; Ha 2003)
Lactoferrin, a major component of whey protein, also acts as an antioxidant (Steijns 2000). It can inhibit the absorption of bacteria through the intestinal wall. Whey protein can activate natural killer cells (Nishiya 1982). In the laboratory, lactoferrin inhibited metastasis of cancer cells in mice (Marshall 2004) and increased IL-2 and natural killer activity (Watanabe 2000).

Minerals

Metallic micronutrients such as copper, zinc (Prasad 2000), and selenium influence the activity of antioxidant enzymes and can reduce oxidative stress. Among children, deficiencies of zinc, copper, and selenium have been linked to immune deficiency and infection (Cunningham-Rundles 2005).
Selenium is involved in several key metabolic pathways (Rotruck 1973; McKenzie 1998, 2000). Glutathione peroxidase, the enzyme that recycles glutathione, depends on the presence of selenium for its antioxidant activity (Arthur 2003). Although plant food is a major dietary source of selenium (eg, garlic is rich in selenium), the highest concentration of dietary selenium occurs in meat.
Zinc deficiency is linked to impaired immune function, partly because of decreased T lymphocyte and B lymphocyte function. Zinc has shown the ability to decrease inflammation and the production of IL-2 (Tanaka 2005). Copper and zinc together have been shown to stimulate internally produced antioxidants such as glutathione and superoxide dismutase (SOD) (Kuppusamy 2005).

DHEA and Immune Function

Dehydroepiandrosterone (DHEA) is produced by the adrenal glands. DHEA has over 100 metabolites and is used by the body for estrogen and testosterone production.
Blood levels of DHEA rise until they peak in the third decade of life, then rapidly decline. Endocrinologists and anti-aging researchers have been focusing on this decrease in DHEA, which in turn produces a decline in other steroidal hormones.
Animal experiments suggest that DHEA has many biological effects, including anticancer, immune-enhancing, neurotrophic, and general anti-aging effects (Bovenberg 2005). A recently published review article of DHEA supplementation in men found convincing research showing positive effects of DHEA on the cardiovascular system, body composition, skin, central nervous system, sexual function, and immune system (Saad 2005).
On the cellular level, DHEA exerts its actions on peripheral target tissues either indirectly (following its conversion to androgens, estrogens, or both) or directly, as a steroid hormone (Perrini 2005). Lower DHEA levels are associated with decreased production of IL-2 and an increase in the presence of IL-6, which is a pro-inflammatory cytokine (Hammer 2005). A study was performed on younger and older men to compare DHEA blood levels and peripheral blood mononuclear cells (PBMCs) in populations of varying ages. The results showed significant changes in sex steroid metabolism by human PBMCs with aging, which may represent a link to age-associated changes in the immune system (Hammer 2005).
Immunomodulatory effects of DHEA in various autoimmune diseases have been studied. Relative reductions in DHEA have been noted in patients with rheumatoid arthritis, systemic lupus erythematosus, HIV and AIDS, sepsis, and trauma (Chen 2004). Overall, DHEA blood levels have been used as diagnostic factors in evaluating the impact of aging on the immune system. Supplemental DHEA has been clinically valuable when used to restore youthful hormonal blood levels in aging, stressed, and immune-compromised individuals (Valenti 2004).
One of DHEA's metabolites, 7-keto DHEA, has also been studied for its ability to support the immune system. A study found that four weeks of 7-keto DHEA supplementation improved immune function in elderly men and women (Zenk 2004). In this randomized, double-blind, placebo-controlled study, 22 women and 20 men over the age of 65 took either 100 mg of 7-keto twice daily or a placebo. The 7-keto group had a significant decrease in immune suppressor cells and a significant increase in immune helper cells. The 7-keto group also saw reductions in diastolic blood pressure and an increase in neutrophils, the first white blood cells to respond to infection.

Polyunsaturated Fatty Acids

Polyunsaturated fatty acids, such as the omega-3 fatty acids found in fish oil and flaxseed oil, have been studied for their anti-inflammatory action (Kaminogawa 2004). Polyunsaturated fatty acid reduces the inflammatory response caused by TNF-α (Johnson 1993; Pedersen 2000).
Most people in the United States have an imbalance in the ratio of omega-3 to omega-6 fatty acids because of diets high in animal fat and vegetable oils high in omega-6 (eg, corn oil). This imbalance has been associated with inflammation (Calder 1997). The ratio can be improved by taking supplemental omega-3 fatty acids. Omega-3 fatty acids have also been shown to:
  • Counteract suppression of the cellular immune system (Pedersen 2000)
  • Suppress TNF-α production and have an anti-inflammatory effect (Grimble 2002)

Probiotics

The gastrointestinal tract relies on live bacteria (microflora) to help support a robust immune response. These probiotic bacteria help prevent foreign bacteria and allergens from passing through the intestinal wall and are important to the overall health of the intestinal immune system (Marteau 2001; Conway 1987; Robins-Brown 1981). Probiotics are found in foods such as yogurt and kefir, which enhance the microflora in the gut by providing additional probiotic bacteria (Fuller 1991; Isolauri 2001). The most commonly used probiotic bacteria are lactobacillus and bifidobacterium, found in yogurts.
Probiotics also strengthen the intestinal immunological barrier. Lactobacillus stimulates natural immunity by improving phagocytic and natural killer immune cell activity (Kaminogawa 2004).

Grape Seed Extract

Chemicals in grape seeds known as proanthocyanidins have potent antioxidant and immune-boosting properties (Ashraf-Khorassani 2004; Bagchi 1997; Bagchi 1998). They increase the activity of internal antioxidants such as glutathione and SOD (Peng 2000).
The antioxidants in grape seed extract are twice as potent as vitamin E and four times as potent as vitamin C (Bagchi 1997; Bagchi 1998). In laboratory studies, proanthocyanidins increased the power of natural killer cells, enhanced the production of IL-2, and decreased production of IL-6 (Cheshier 1996).

Green Tea Extract

Green tea extract, which contains a class of compounds known as catechins, has become increasingly popular as scientists learn more about its antioxidant and free radical–scavenging abilities. One of the most potent catechins in green tea is epigallocatechin-3-gallate (Chen 2002). Green tea extract is also rich in vitamins C and B (Hasegawa 2002; Hasegawa 1998).
Green tea has a positive influence on lipid metabolism and exerts anticancer effects. Green tea modulates the inflammatory processes and protects against DNA damage (Lin 1998). The catechins from green tea demonstrate considerable antioxidant activity (Chen 2002) and are potent free radical scavengers (Zhong 2003; Jimenez-Lopez 2004).

Hyperimmune Egg Extract

Hyperimmune egg extracts provide unique immune protection. Long ago, agricultural scientists discovered that they could immunize hens against germs that threaten humans. This immunity was then passed on by the hen to her egg (Dias da Silva 2010; Dean 2000; Cama 1991). Concentrated protein extracts from those so-called “hyperimmune eggs” confer some immunity to humans who consume them (Fujibayashi 2009; Sarker 2001).

Andrographis

Healers in Asia and India have long prescribed the bitter herb Andrographis paniculata for the treatment of ailments ranging from infections and inflammation to colds and fevers (Ji 2005). Researchers have isolated a number of the herb’s active ingredients. Chief among these are andrographolides, which are phytochemicals believed to exert their effects, in part, on tissues of the blood cell-producing bone marrow and/or spleen. One such compound, andrographanin, enhances the ability of certain white blood cells to recognize and neutralize foreign cells (eg, tumor cells and viruses) (Ji 2005).

Beta Glucan

Beta glucans can naturally boost the immune system by optimizing its response to diseases and infections. Because the body does not produce beta glucans naturally, the only way to get them is through outside sources. Studies have shown that beta glucans act as immunomodulator agents, meaning they trigger a cascade of events that help regulate the immune system, making it more efficient. Specifically, beta glucans stimulate the activity of macrophages, which are versatile immune cells that ingest and demolish invading pathogens and stimulate other immune cells to attack (National Institute of Allergy and Infectious Diseases 2012). Macrophages also release cytokines, chemicals that when secreted enable immune cells to communicate with one another. In addition, beta glucans stimulate lethal white blood cells (lymphocytes) that bind to tumors or viruses, and release chemicals to destroy it.

Life Extension Suggestions


In addition, the following blood tests may provide helpful in formation:
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This information (and any accompanying material) is not intended to replace the attention or advice of a physician or other qualified health care professional. Anyone who wishes to embark on any dietary, drug, exercise, or other lifestyle change intended to prevent or treat a specific disease or condition should first consult with and seek clearance from a physician or other qualified health care professional. Pregnant women in particular should seek the advice of a physician before using any protocol listed on this website. The protocols described on this website are for adults only, unless otherwise specified. Product labels may contain important safety information and the most recent product information provided by the product manufacturers should be carefully reviewed prior to use to verify the dose, administration, and contraindications. National, state, and local laws may vary regarding the use and application of many of the treatments discussed. The reader assumes the risk of any injuries. The authors and publishers, their affiliates and assigns are not liable for any injury and/or damage to persons arising from this protocol and expressly disclaim responsibility for any adverse effects resulting from the use of the information contained herein.
The protocols raise many issues that are subject to change as new data emerge. None of our suggested protocol regimens can guarantee health benefits. The publisher has not performed independent verification of the data contained herein, and expressly disclaim responsibility for any error in literature.


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