DIETS HIGH IN SALT MAY INCREASE RISK OF AUTOIMMUNE DISEASES

Eating a diet high in sodium may do more than raise your blood pressure. Researchers report that it could also contribute to the development of autoimmune diseases, where the body's immune system mistakenly mounts an attack upon some part of the body.  Three new studies conducted on mice and human immune cell cultures, suggest salt may be a prime suspect in a wide range of autoimmune diseases, including multiple sclerosis (MS), psoriasis, rheumatoid arthritis and ankylosing spondylitis (arthritis of the spine).

Significant increases in the incidence of autoimmune diseases, especially multiple sclerosis and type 1 diabetes, suggests that environmental and lifestyle factors, and not just genetics, influence the onset of these diseases. Observational studies have shown that persons who eat more meals out and especially those who frequently eat fast food, have high levels of pathogenic helper T-cells (specifically helper T-cells 17),which are elevated in autoimmune diseases.  Helper T-cells 17 are a type of infection-fighting cell that is likely to become pathogenic, attacking tissues in the body rather than infectious agents. To investigate if high salt intake was possibly increasing these cell levels, Dr. David Hafler and his colleagues as well as researchers at other institutions, fed high salt diets to mice and exposed cultures of human T-cells to elevated levels of sodium.  In both cases, in the presence of sodium, helper T-cells differentiated into the pathogenic helper T-cells 17 at ten times the rate of those not exposed to high levels of sodium.  In fact,  the mice on high salt diets developed a severe form of multiple sclerosis, called autoimmune encephalomyelitis. 

While salt may play a role in autoimmune diseases, the researchers said the picture is most likely complicated. "We don't think salt is the whole story. It's a new, unexplored part of it, but there are hundreds of genetic variants involved in autoimmune disease and environmental factors, too," said Hafler.  In addition to salt, other factors have been shown to influence levels of pathogenic helper T-cells, including microbes, diet, metabolism, environmental factors and cytokines (proteins that help regulate inflammatory responses).

What to do:  While the relationship between salt and autoimmune disease has yet to be conclusively explored, there are plenty of other health benefits to limiting sodium intake.  High salt diets have been shown to raise blood pressure which increases risk for stroke, heart disease, and kidney disease.  High salt intake also is detrimental to bone health.   Daily sodium intake should be less than 2,300 mg of sodium a day (about 1 teaspoon of salt).  Limit your meals out because these are almost always high in sodium.  At home use lemon, herbs, and spices instead of salt to season foods.  Read labels to assess the sodium content of foods as most of our intake comes from salt added by manufacturers.  Deli meats, frozen dinners, boxed noodle and rice dishes, canned soups, canned vegetables, bottled dressings & sauces, bread, and snack foods all tend to be high in sodium. 

Adapted from article available at:

http://www.nlm.nih.gov/medlineplus/news/fullstory_134647.html

http://www.examiner.com/article/can-too-much-dietary-salt-set-families-up-for-developing-autoimmune-diseases

Sources: 

Kleinewietfeld M, Manzel A, Titze J, Kvakan H, Yosef N, et al.  Sodium chloride drives autoimmune disease by the induction of pathogenic TH17 cells.  Nature (06 March 2013)|doi:10.1038/nature11868.  Available at: http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11868.html?WT.ec_id=NATURE-20130307

Wu C, Yosef N, Thalhamer T, Zhu C, Xiao S et al.  Induction of pathogenic TH17 cells by inducible salt-sensing kinase SGK1.  Nature (06 March 2013) | doi:10.1038/nature11984. Available at: http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11984.html

Yosef N, Shalek AK, Gaublomme JT, Jin H, Lee Y, et al.  Dynamic regulatory network controlling TH17 cell differentiation.  Nature (06 March 2013) | doi:10.1038/nature11981. Available at: http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11981.html

EVEN A DRINK A DAY BOOSTS RISK FOR CANCER AS WELL AS DANGEROUS IRREGULAR HEARTBEAT

Two new studies indicate that even very moderate alcohol intake can prove detrimental to our health.  In the first study, researchers found that intake as low as a drink a day increases the risk of dying from cancer, and, in the second, it was found that among those with heart disease, very moderate intake increases risk for atrial fibrillation, an irregular heart rhythm that can lead to stroke and/or heart failure.   

In the cancer study, researchers analyzed cancer mortality and alcohol intake data in the U.S. from 2009-2010 and found that 1 in every 30 cancer deaths can be attributed to alcohol consumption.  While heavy drinking increases cancer risk more than moderate intake, as much as 30% of all alcohol-related cancer deaths are linked to drinking 1 ½ or less drinks per day.   Alcohol appears to be an especially important risk factor for breast cancer where 1 in every 6 breast cancer deaths has been attributed to the increased risk that comes from alcohol consumption.  

Commenting on the study findings, lead investigator Dr. David Nelson stated “Alcohol is a cancer-causing agent that's in plain sight, but people just don't see it.  Moderate drinking has been associated with heart benefits, but, in the broader context of all the issues and all the problems that alcohol is related to, alcohol causes 10 times as many deaths as it prevents.  There is really no safe level of alcohol use.” 

Previous studies have shown drinking is a risk factor for cancers of the mouth, throat, esophagus, liver, colon, rectum and, in women, breast cancer.  It is believed alcohol acts as a chemical irritant to sensitive cells, impeding their DNA repair as well as increasing their vulnerability to other carcinogens such as tobacco smoke.  In women, alcohol’s impact on estrogen levels and estrogen receptors is believed to drive increases in breast cancer rates.   

Another recent study found that moderate alcohol consumption increases risk of experiencing atrial fibrillation (a-fib) among those with heart disease or diabetes.  Binge drinking has long been known to increase episodes of a-fib but the effect that moderate alcohol consumption has on rates of a-fib has been debated. 

Several studies have suggested that moderate alcohol intake - up to one drink a day for women, up to two for men can help to prevent coronary heart disease - where cholesterol-containing "plaque" builds up in the arteries.  However, this latest study suggests that when people already have heart issues, moderate drinking is actually tied to more A-fib cases. For five years, the study tracked more than 30,000 older adults who either had clogged arteries, a history of stroke, or diabetes with heart health problems. Most had coronary heart disease.  Researchers found that even after controlling for age, weight, and cigarette smoking, compared to those who abstained, those who were moderate alcohol consumers had a 14% increased risk for a-fib. 

Commenting on the findings, lead researcher Dr. Yan Liang wrote, “In general, experts say that if you're already a moderate drinker it's probably okay to keep it up.  But, for people with certain chronic health problems, the new results may question that guidance.  Our findings suggest that older individuals with cardiovascular disease or diabetes should probably limit their alcoholic beverages to no more than 1 drink per week".

What to do:  If you already abstain, continue to do so.  If you already have irregular heartbeat, a-fib, a history of stroke, congestive heart failure, or advanced heart disease it is usually advised that you avoid alcohol.  If you do not have advanced heart disease and you choose to drink alcohol, do so in moderation.  Even infrequent binge drinking has been shown to detrimental.  Moderate drinking means having up to one drink a day for women and up to two for men.  One drink is defined as 0.6-fluid ounces of pure alcohol which translates into about 10-ounces of beer, 4-ounces of wine or 1 ¼ ounces of liquor.  The antioxidants in red wine, believed to confer some of its associated heart health benefits, are also found in grapes, grape juice, blueberries, blackberries, mulberries, peanuts, and pistachios.

Adapted from articles available at:

http://vitals.nbcnews.com/_news/2012/10/03/14204194-moderate-drinking-linked-to-abnormal-heart-rhythm?lite

http://www.reuters.com/article/2012/10/03/us-moderate-drinking-idUSBRE89213L20121003

http://www.nlm.nih.gov/medlineplus/news/fullstory_134037.html

Sources:

Nelson DE, Jarman DW, Rehm J, Greenfield TK, Rey G, Kerr WC, Miller P, Shield KD, Ye Y, Naimi TS. Alcohol-attributable cancer deaths and years of potential life lost in the United States. American Journal of Public Health, Feb. 14, 2013, doi: 10.2105/AJPH.2012.301199

Available at: http://ajph.aphapublications.org/doi/abs/10.2105/AJPH.2012.301199?journalCode=ajph

Liang Y, Mente A, Yusuf S, Gao P, Sleight P, Zhu J, Fagard R, Lonn E, Teo KK, Alcohol consumption and the risk of incident atrial fibrillation among people with cardiovascular disease.  CMAJ October 1, 2012, doi:10.1503/cmaj.120412  Available at http://www.cmaj.ca/content/early/2012/10/01/cmaj.120412.abstract

MANY VITAMIN D SUPPLEMENTS DO NOT CONTAIN LEVELS CLAIMED ON LABEL

Unlike prescription medications, the U.S. Food and Drug Administration does not routinely test to verify that nutritional supplements such as vitamins and minerals actually contain what their labels claim.  Numerous studies that have analyzed the contents of mainstream brands of supplements have found significant differences between the nutrient levels actually in the supplement and the amounts listed on labels.  A recent study that focused on vitamin D supplements again found that some contained a lot more vitamin D than the label stated while others contained markedly less.

In the new study, researchers analyzed 55 over-the-counter bottles of vitamin D supplements from 12 major manufacturers. They also tested vitamin D pills made at a compounding pharmacy, which creates individualized drugs. The manufacturers were unidentified.  Overall, the amount of vitamin D found in the supplements ranged from 9% to 146% percent of what was listed on the label.

The study found that the supplements produced by the compounding company were the least reliable while the manufacturers with the USP seal (which means their supplements’ contents are verified by the non-profit U.S. Pharmacopeial Convention) had the most reliable supplements. 

In recent years, use of vitamin D supplements has been rapidly growing.  It has been increasingly recognized that many Americans are deficient in vitamin D.  Low vitamin D is a concern because research has linked low levels to bone disease and a likely increased risk of diabetes, heart disease, low thyroid function, poor immune function, and some cancers.  Vitamin D is made naturally when our skin is exposed to the sun but too much sun exposure increases risk of skin cancer.  Some vitamin D is also available in foods such as milk and other fortified products, fatty fish oil, and sardines and other fish that contain bones.  Most at risk for low vitamin D are those who are elderly, obese, have dark skin, and/or live in locations farther from the equator (such as New York). 

What to do:  Vitamin D levels can be tested with your routine bloodwork.  Follow your doctor’s advice on supplementation.  If you have been taking a supplement for several months and do not see a rise in your vitamin D level, you may need to switch supplements.  When choosing supplements, opt for widespread brands because they are more likely to be tested than smaller brands.  Notably, in tests by Consumer Labs, price does not appear to correspond with quality.  Also, consider looking for the USP seal.  Some supplements that are USP certified include Sunmark, TruNature, Kirkland, Nature Made, and Berkley & Johnson.

Source:  LeBlanc ES, Perrin N, Johnson JD, Ballatore A , Hillier T.  Over-the-counter and compounded vitamin D: Is potency what we expect? JAMA Intern Med,  Feb 11, 2013; doi:10.1001/jamainternmed.2013.3812.  Available at: http://archinte.jamanetwork.com/article.aspx?articleid=1570096

Adapted from article available at:  http://www.nlm.nih.gov/medlineplus/news/fullstory_133910.html