Viruses have nothing to do with chronic fatigue syndrome (CFS), despite earlier evidence of a link, a study has shown.

The new findings deepen the mystery surrounding the cause of debilitating condition, also known as myalgic encephalomyelitis (ME).

Scientists dismissed previous claims that two viruses, known as XMRV and pMLV, may underlie CFS.

"The bottom line is we found no evidence of infection with XMRV and pMLV," said Dr Ian Lipkin, a member of the research team from Columbia University in New York City. "These results refute any correlation between these agents and disease."

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  • How To Fight Fatigue

  • Stay Hydrated

    "We actually become stressed when we're dehydrated, particularly if alcohol is consumed, so aim for 1-2 litres a day; and cut back on caffeine which is an artificial form of adrenaline and can affect sleep patterns leaving you jittery and anxious - you should avoid caffeine altogether after 3pm." Sleep and Energy Coach at <a href="http://www.nightingalehospital.co.uk/" target="_hplink">Capio Nightingale Hospital</a>, <strong>Dr. Nerina Ramlakhan</strong>.

  • Eat Mindfully

    "Although many of us think we are eating healthy, that diet can make us fatigued. Most "healthy" meals are explained away as oatmeal for breakfast with fruit, lettuce with greens for lunch, brown rice with what ever for dinner. Those same people say they dont eat carbs. Let me make this quite clear..... fruits and vegetables and grains are carbohydrates. Start your day with a protein, eggs, cheese, yogurt, even almond butter and you wont crash thru out the rest of the day." <strong>Dr Eva Cwynar</strong>, author of <a href="http://www.amazon.co.uk/The-Fatigue-Solution-Increase-Energy/dp/1848508131/ref=sr_1_1?s=books&ie=UTF8&qid=1340970870&sr=1-1" target="_hplink"><em>The Fatigue Solution</em></a>.

  • Go Nuts

    "Have a handful of nuts mid-morning and mid-afternoon, the most common slump-times, to provide a lovely hit of protein to balance blood sugar levels. Raid the snack bowl of almonds, or hazelnuts, then add a piece of fruit for natural fructose for a natural energy boost." Director of <a href="http://www.vitality4life.co.uk/" target="_hplink">Vitality4Life</a>, <strong>Ricky Hay</strong>.

  • Drink Coffee

    "Coffee can actually help boost your adrenal glands (which are burnt out in most of us and the main culpret for fatigue). Coffee, yes, good but only 1/2 cup and only in the morning. Most than that or at a different time puts your hormones into hydharmony and then just like many recreational drugs, we want more and more and it becomes less and less effective." <strong>Dr Eva Cwynar</strong>, author of <a href="http://www.amazon.co.uk/The-Fatigue-Solution-Increase-Energy/dp/1848508131/ref=sr_1_1?s=books&ie=UTF8&qid=1340970870&sr=1-1" target="_hplink"><em>The Fatigue Solution</em></a>.

  • Keep On Moving

    "Don't stop moving! Make time to go and get some fresh air either for a run, jog or walk. Take full advantage of the sunnier weather and lighter evenings, wrap up to go outside and spend 5 minutes at the beginning of your day exercising and you will feel good for the rest of the day." Personal trainer, <a href="www.nuffieldhealth.com/Individuals/.../Ismail-K-M/" target="_hplink"><strong>Khalid Ismail</strong></a>.

  • Maintain Healthy Nutrition

    "Eat breakfast every morning within 30 minutes of rising to kick start your energy and metabolism and minimise production of adrenaline - it also helps burn any extra calories consumed during the day more efficiently. This will give you bundles of energy to tackle to day ahead." Sleep and Energy Coach at <a href="http://www.nightingalehospital.co.uk/" target="_hplink">Capio Nightingale Hospital</a>, <strong>Dr. Nerina Ramlakhan</strong>.

  • Don't Have Unrealistic Expectations

    "If you're a busy, working mum or person, you'll only have feelings of disappointment and stress if you have high expectations of your day ahead. To alleviate stress and anxiety, try to accept the fact that things will go wrong. "Kids may have a meltdown, dinner may not come out as perfectly as you hope, people may demand your time. Being prepared for imperfection can help reduce everyday stress." Life coach, <strong><a href="http://www.sophiadavis.co.uk/" target="_hplink">Sophia Davis</a></strong>.

  • Sleep!

    "Recharge you batteries over by getting good rest and exercise, topping up good quality sleep with power naps if possible - research has shown that these naps re-balance the immune and nervous systems." Sleep and Energy Coach at <a href="http://www.nightingalehospital.co.uk/" target="_hplink">Capio Nightingale Hospital</a>, <strong>Dr. Nerina Ramlakhan</strong>.

  • Drink (Green) Tea

    "Green tea and ginseng tea are great energy boosters. Green tea contains antioxidant properties to fight free radicals." Health and Beauty Expert, <a href="http://www.tinarichards.com/" target="_hplink"><strong>Tina Richards</strong></a>.

  • Steer Clear Of 'Bad Sugars'

    "Stay away from artificial sweeteners. Sugar substitutes like stevia and zylitol are fine, even good for you, but compounds containing substances such as aspartame can ruin the integrity of your gut and create chaos. Digestion gets slowed, bloating occurs, bowel movements become chaotic and fatigue sets in. No diet drinks..... ever." <strong>Dr Eva Cwynar</strong>, author of <a href="http://www.amazon.co.uk/The-Fatigue-Solution-Increase-Energy/dp/1848508131/ref=sr_1_1?s=books&ie=UTF8&qid=1340970870&sr=1-1" target="_hplink"><em>The Fatigue Solution</em></a>.

CFS can strike out of the blue - causing severe tiredness as well as muscle weakness, aches and pains, memory loss, and poor sleep.

Once dismissed as a purely psychological problem, experts now agree that it is a serious physical illness.

In 2009 and 2010, separate studies found the two viruses in the blood of CFS patients, raising hopes of identifying an easily treatable cause of the condition. But since then, other investigators have been unable to confirm the results.

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"We went ahead and set up a study to test this thing once and for all and determine whether we could find footprints of these viruses in people with chronic fatigue syndrome or in healthy controls," said Dr Lipkin.

The research, published in the American Society for Microbiology's online journal mBio, involved comparing 147 diagnosed patients with CFS and 146 healthy individuals.

Blood samples were tested for genes specific to XMRV and pMLV, as had been done before. But great care was taken to ensure no contamination of the testing chemicals which may have led to false results in the earlier studies.

See also:

Chronic Fatigue Syndrome Treatments 'Good Value'

Chronic Fatigue May Be Causing Hundreds Of Children To Miss School

XMRV and pMLV are viruses commonly found in mice, but there has never been a definite case of them infecting humans.

The tests found no evidence of the two viruses in the blood of either CFS patients or healthy participants.

Dr Lipkin said: "We've tested the XMRV/pMLV hypothesis and found it wanting. We are not abandoning the science. The controversy brought a new focus that will drive efforts to understand CFS/ME and lead to improvements in diagnosis, prevention and treatment of this syndrome."

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    Scientists from the <a href="http://www.northwestern.edu/" target="_hplink">Northwestern University</a> in Chicago have come one step closer to developing a potential cure for peanut allergies, by creating an immune system tolerant to peanuts. The researchers found that they can switch off potentially deadly peanut allergy attacks by tricking the immune system into tolerating nut proteins, and not seeing them as a threat to the body. <strong><a href="http://www.huffingtonpost.co.uk/2011/10/11/peanut-allergies-has-a-cure-been-found_n_1004615.html" target="_hplink">Read the full story here</a></strong>.

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Patients with CFS have benefited from cognitive behaviour therapy (CBT), which teaches people to change the way they think, and structured exercise programmes.

Often patients spontaneously recover after years with the condition, or learn to live with their symptoms.