A surprising link has been found between long life spans and naturally low levels of vitamin D.

Scientists made the discovery after studying data on 380 families with members who survived into their nineties.

Previous research has shown that people lacking the "sunshine vitamin" are more at risk from a host of conditions including heart disease, diabetes, cancer, allergies and mental illness.

According to these studies, having too little vitamin D increases the chances of premature death.

Dutch scientists examined data from the Leiden Longevity Study, which involved families with at least two very elderly siblings - either a brother aged at least 89, or a sister aged 91 and over. A total of 1,038 offspring of the elderly siblings were also included, together with their partners.

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  • 1. Mix Alcohol And Sedatives.

    Mix prescription or illicit drugs with alcohol. <a href="http://www.huffingtonpost.com/ann-brenoff/whitney-houston-prescription-drugs_b_1280439.html" target="_hplink">Even drinking wine with dinner and then taking prescription sleep aides can be a lethal combination</a>. A U.S. Department of Health and Human Services study found 5.8 percent of people age 50 to 59 used illicit drugs in 2010, up from 2.7 percent in 2002.

  • 2. Never Check For Diabetes.

    The number of Americans with Type 2 diabetes is expected to rise from 30 million today to 46 million by 2030, when one of every four boomers -- 14 million -- will be living with this chronic disease, according to the National Center for Chronic Disease Prevention and Health Promotion. <br /> <br />Untreated diabetes can lead to blindness, amputations and clogged arteries that can cause heart attacks and strokes. The test to determine whether you are diabetic is a simple blood test; you should remind your doctor to include it in your annual physical.

  • 3. Pack On The Pounds.

    More than one out of every three boomers -- more than 21 million -- will be considered obese by 2030. Already, we are the demographic with the highest and fastest-growing rate of obesity. As we age, our metabolism slow down and we burn fewer calories -- if we don't alter our eating and exercise patterns, weight gain is inevitable. Obesity can lead to high blood pressure, heart disease, and a host of other life-threatening ailments. <a href="http://www.huffingtonpost.com/ann-brenoff/the-dieting-10-percent-club-losing-weight-after-50_b_1440729.html" target="_hplink">Losing just 10 percent of your body weight</a> has health benefits, so consider that as a goal.

  • 4. Ignore The Signs Of A Heart Attack.

    No chest pain doesn't mean no heart attack. <a href="http://www.webmd.com/heart-disease/features/her-guide-to-a-heart-attack" target="_hplink">Women having heart attacks</a> frequently report experiencing a feeling of indigestion and extreme fatigue, while some men say they feel a fullness or a squeezing pain in the center of the chest, which may spread to the neck, shoulder or jaw. When a diabetic has a heart attack, the pain is often displaced to other areas such as the lower back.

  • 5. Get Minimal Sleep.

    Try as you might, you just can't stay asleep, right? You pass out before "60 Minutes" is over, but then wake up around midnight and count sheep until the alarm goes off. If that sounds like you, you aren't alone. The U.S. Centers for Disease Control and Prevention says that <a href="http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5842a2.htm" target="_hplink">boomers report not getting enough sleep between one and 13 nights each month</a>. <br /> <br />Is it life-threatening? In itself, no. But as soon as you slip behind the wheel bleary-eyed, you are putting yourself and others at risk. Your reflexes are slower, you pay less attention and you could become one of the more than 100,000 Americans who fall asleep at the wheel and crashes each year. And the <a href="http://drowsydriving.org/about/facts-and-stats/" target="_hplink">National Highway Traffic Safety Administration</a> says that's a conservative estimate, by the way. Driver fatigue results in an estimated 1,550 deaths, 71,000 injuries, and $12.5 billion in monetary losses.

  • 6. Avoid Exercise.

    AARP says the minimum you need to stay healthy are muscle-strengthening exercises twice a week plus 2.5 hours a week of moderate activity like walking or 75 minutes a week of a more intense activity like jogging. Exercise is also good for your memory: Just one year of <a href="http://www.aarp.org/health/brain-health/info-02-2011/keep_your_memory_strong_by_walking.html" target="_hplink">walking three times a week can increase the size of the hippocampus</a>, the part of the brain that's key to memory.

  • 7. Carry The World's Burdens On Your Shoulders.

    We're talking about stress with a capital S. Boomers are the sandwich generation, caught in the middle of caring for our parents and our children. We were deeply affected by the recession and <a href="http://www.huffingtonpost.com/ann-brenoff/midlife-crisis-depression-is-ok-the-new-good_b_1470958.html" target="_hplink">boomers have the highest rates of depression</a> by age demographic. Unless we unload, we are going to implode.

  • 8. Carry A Beer Belly And A Caboose.

    It isn't just our extra weight; it's where we carry it. An excess of visceral fat causes our abdomens to protrude excessively. We call it a "pot belly" or "beer belly" or if the visceral fat is on our hips and buttocks, we say we are "apple shaped." Cute names aside, scientists now say that body fat, instead of body weight, is the key to evaluating obesity. And guess what? It's all bad.

  • 9. Continue To Smoke.

    <a href="http://www.gallup.com/poll/128183/smoking-age-baby-boomer-bulge.aspx" target="_hplink">Gallup found that baby boomers between the ages of 44 and 54 reported higher levels of smoking</a> than those immediately younger or those who are older. Hard to imagine that they haven't gotten the word yet about the risks cigarettes carry.

  • Drink Too Much.

    "Alcohol does all kinds of things in the body, and we're not fully aware of all its effects,"<a href="http://www.webmd.com/mental-health/alcohol-abuse/features/12-health-risks-of-chronic-heavy-drinking" target="_hplink"> James C. Garbutt, MD, professor of psychiatry at the University of North Carolina at Chapel Hill School of Medicine told WebMD</a>. "It's a pretty complicated little molecule." Among the risks of drinking too much: Higher risk of cancer, heart disease, cirrhosis of the liver, dementia, depression and high blood pressure. Drink in moderation: <a href="http://www.huffingtonpost.com/2012/05/07/red-wine-benefits-anti-aging-tips_n_1475079.html" target="_hplink">Red wine, in particular, has been found to increase longevity</a>. The Mayo Clinic <a href="http://www.mayoclinic.com/health/red-wine/hb00089" target="_hplink">defines moderation as "an average of two drinks a day for men and one drink a day for women</a>."

Vitamin D is created in the skin by the action of sunlight, and also obtained from food or supplements, but genetic factors also influence blood levels in different individuals.

The scientists looked at the influence of genetic code alterations known as single nucleotide polymorphisms (SNPs) in three genes associated with vitamin D levels.

The authors, led by Dr Diana van Heemst, from Leiden University Medical Centre, wrote: "We found that the offspring of nonagenarians who had at least one nonagenarian sibling had lower levels of vitamin D than controls, independent of possible confounding factors and SNPs associated with vitamin D levels."

Offspring of long-lived individuals were also less likely to have a common genetic variant in a gene called CYP2R1, which predisposes people to high levels of vitamin D.

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Vitamin D is known to be vital for healthy bones and teeth. But the new results throw doubt on the idea that low levels of the vitamin in the blood can lead to a wide array of health problems, according to the researchers. Previous studies have tended not to show whether low vitamin D caused disease or resulted from it, they say.

"Cross-sectional and longitudinal studies have linked low serum levels of vitamin D to a higher risk of death, cardiovascular disease and cognitive decline," the scientists wrote. "Because of limitations in the design of these studies, it was not possible to infer a causal relation between vitamin D and outcome.

"In the case of mortality, low serum vitamin D levels might be a marker of frailty, because ill patients are expected to spend less time outdoors and may have inadequate nutrition."

The new research suggested that naturally low levels of vitamin D may go hand-in-hand with a genetic resistance to ageing.

Their findings are reported in the Canadian Medical Association Journal.

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  • Take regular exercise

  • Engage socially with others

  • Have a positive attitude about ageing

  • Eat a healthy diet

  • Protect your eyes

  • Don’t smoke

  • Get regular health checkups

  • Avoid excessive sun exposure

  • Get sufficient, good-quality sleep

  • Pay attention to your pension, and get expert financial advice