Addiction researchers at Washington University School of Medicine in St. Louis have found that a risk for alcoholism also may put individuals at risk for obesity. The researchers noted that the association between a family history of alcoholism and obesity risk has become more pronounced in recent years. Both men and women with such a family history were more likely to be obese in 2002 than members of that same high-risk group had been in 1992. “In addiction research, we often look at what we call cross-heritability, which addresses the question of whether the predisposition to one condition also might contribute to other conditions,” says first author Richard A. Grucza, PhD. “For example, alcoholism and drug abuse are cross-heritable. This new study demonstrates a cross-heritability between alcoholism and obesity, but it also says — and this is very important — that some of the risks must be a function of the environment. The environment is what changed between the 1990s and the 2000s. It wasn’t people’s genes.”
Obesity in the United States has doubled in recent decades from 15 percent of the population in the late 1970s to 33 percent in 2004. Obese people – those with a body mass index (BMI) of 30 or more – have an elevated risk for high blood pressure, diabetes, heart disease, stroke and certain cancers.
Reporting in the Archives of General Psychiatry, Grucza and his team say individuals with a family history of alcoholism, particularly women, have an elevated obesity risk. In addition, that risk seems to be growing. He speculates that may result from changes in the food we eat and the availability of more foods that interact with the same brain areas as addictive drugs. “Much of what we eat nowadays contains more calories than the food we ate in the 1970s and 1980s, but it also contains the sorts of calories — particularly a combination of sugar, salt and fat — that appeal to what are commonly called the reward centers in the brain,” says Grucza, an assistant professor of psychiatry. “Alcohol and drugs affect those same parts of the brain, and our thinking was that because the same brain structures are being stimulated, overconsumption of those foods might be greater in people with a predisposition to addiction.”
Grucza hypothesized that as Americans consumed more high-calorie, hyper-palatable foods, those with a genetic risk for addiction would face an elevated risk from because of the effects of those foods on the reward centers in the brain. His team analyzed data from two large alcoholism surveys from the last two decades. The National Longitudinal Alcohol Epidemiologic Survey was conducted in 1991 and 1992. The National Epidemiologic Survey on Alcohol and Related Conditions was conducted in 2001 and 2002. Almost 80,000 people took part in the two surveys.
“We looked particularly at family history of alcoholism as a marker of risk,” Grucza explains. “And we found that in 2001 and 2002, women with that history were 49 percent more likely to be obese than those without a family history of alcoholism. We also noticed a relationship in men, but it was not as striking in men as in women.” Grucza says a possible explanation for obesity in those with a family history of alcoholism is that some individuals may substitute one addiction for another. After seeing a close relative deal with alcohol problems, a person may shy away from drinking, but high-calorie, hyper-palatable foods also can stimulate the reward centers in their brains and give them effects similar to what they might experience from alcohol.
“Ironically, people with alcoholism tend not to be obese,” Grucza says. “They tend to be malnourished, or at least under-nourished because many replace their food intake with alcohol. One might think that the excess calories associated with alcohol consumption could, in theory, contribute to obesity, but that’s not what we saw in these individuals.” Grucza says other variables, from smoking, to alcohol intake, to demographic factors like age and education levels don’t seem to explain the association between alcoholism risk and obesity. “It really does appear to be a change in the environment,” he says. “I would speculate, although I can’t really prove this, that a change in the food environment brought this association about. There is a whole slew of literature out there suggesting these hyper-palatable foods appeal to people with addictive tendencies, and I would guess that’s what we’re seeing in our study.” The results, he says, suggest there should be more cross-talk between alcohol and addiction researchers and those who study obesity. He says there may be some people for whom treating one of those disorders also might aid the other.
In the past, positive blood and skin tests would often be mistaken for a food allergy because they would indicate the presence of immunoglobulin E antibodies, but it is important to remember that these are typically higher in patients with atopic dermatitis, according to a speaker at the 69th Annual American Academy of Dermatology Meeting conducted in New Orleans this week. “Those antibodies are not diagnostic, and the only way to diagnose food allergy is with a strong history of reactions or a challenge,” Jon M. Hanifin, MD, of Oregon Health & Science University, said in a press release. “This is done in a doctor’s office, using small increments of the food in question and increasing the amount until an allergic reaction occurs or does not occur. Usually a parent can pinpoint if a child has a true food allergy because the allergic reaction will appear so quickly with lip swelling or hives, quite distinct from simply food intolerance.”
Between 6% and 10% of children have atopic dermatitis, and about one-third of these children have food allergy. Recent research examining the genetic basis of atopic dermatitis has shown that this chronic skin condition is likely related to a defect in the epidermal barrier, which allows irritants, microbes and allergens (such as food) to penetrate the skin and cause adverse reactions. Because the skin barrier in patients with atopic dermatitis is compromised and open to absorb proteins, it allows sensitization to certain foods, leading to a positive skin or blood test.
New guidelines recently issued by the National Institute of Allergy and Infectious Diseases established a protocol for the proper evaluation and management of food allergy. The guidelines recommend that children who are younger than aged 5 years with moderate to severe atopic dermatitis be considered for food allergy evaluation if they have persistent atopic dermatitis despite optimized management or if the child has a reliable history of an immediate reaction after eating a specific food.
Hanifin said research is also ongoing into whether withholding foods is leading to more allergies than an unrestricted diet in young children. This may provide future insight in potential ways to prevent food allergies. He said children in Israel seldom get peanut allergy, which may potentially be attributed to the use of peanut proteins in pacifiers in that country. In the United States and Europe, where peanut allergies are more common, infants are not usually exposed to this food until they are toddlers – the time when most peanut allergies are noticed.
“There is some thinking that withholding foods might actually be causing more allergies, and that an unrestricted diet may help tolerize babies to foods that could potentially cause a problem later in life,” Hanifin said. “Ongoing studies in this country using oral immunotherapy appear promising, and physicians hope that we may discover how to prevent food allergies in the future while continuing to provide successful treatment for children with atopic dermatitis.”
Source: Hanifin J. Food allergy and dermatology. Presented at: The American Academy of Dermatology 69th Annual Meeting; Feb. 4-8, 2011; New Orleans
“It may be that the amount of omega-3 fatty acids in fish oil supplements are higher than most people would typically get from their diet,” White said.
However, White cautioned against gleaning any recommendations from the results of one study.
“Without confirming studies specifically addressing this,” she said, “we should not draw any conclusions about a causal relationship.”
Edward Giovannucci, M.D., Sc.D., professor of nutrition and epidemiology at the Harvard School of Public Health and an editorial board member of Cancer Epidemiology, Biomarkers & Prevention, agreed.
“It is very rare that a single study should be used to make a broad recommendation,” said Giovannucci. “Over a period of time, as the studies confirm each other, we can start to make recommendations.”
Still, fish oil continues to excite many, as evidence emerges about its protective effect on cardiovascular disease and now cancer.
Harvard researchers are currently enrolling patients for the randomized Vitamin D and Omega-3 Trial (also called VITAL), which will assess the impact of fish oil supplements and vitamin D on cancer, heart disease and stroke.
The researchers plan to enroll 20,000 U.S. men aged 60 years and older and women aged 65 years and older who do not have a history of these diseases and have never taken supplements.
Kidney stones are small, hard deposits of minerals and salts that can form in the kidneys when urine becomes concentrated. Specific treatment beyond increasing water intake is usually not needed, but a kidney stone can be very painful to pass, as anyone who has had one can tell you. While anyone can get kidney stones, there are multiple risk factors that can potentially increase your chances of acquiring them, including:
- Family history of kidney stones.
- Being over 40 years old.
- Being male.
- High protein, high sodium and high sugar diets.
- Being obese.
- Digestive diseases such as inflammatory bowel disease or surgeries such as gastric bypass.
You can reduce your risk of getting kidney stones by:
- Drinking water throughout the day. For those with a history of kidney stones, doctors usually recommend passing approximately 2.5 litres of urine daily. In summer months you need to consume considerably more fluids to stay well-hydrated.
- Eating fewer foods containing high amounts of oxalate. Kidney stones can form due to a build up of calcium oxalate. Foods rich in oxalate include spinach, beets, rhubarb, okra, tea, chocolate and soy products.
- Limiting salt and animal protein in your diet. Reduce the amount of salt in your diet and choose non-animal protein sources such as nuts to reduce your chances of getting kidney stones.
- Watching out for stealth sources of sodium. Some energy and sports drinks contain high levels of sodium and/or caffeine. While they may quench your thirst, you may also be increasing your risk of stone formation.
- Re-hydrating often if engaged in strenuous activity if you have long-term exposure to the heat. Painters, roofers, landscapers, marathon runners and people who enjoy outdoor sports activities that last several hours at a time need to pay special attention to their water intake and watch for signs of dehydration. Health experts recommend at least 16 to 32 ounces of water per hour of heat exposure. A lack of sweat or urination, dizziness, weakness, headache, muscle cramps, nausea or vomiting are possible signs of heat-related illness or dehydration.
- Avoiding calcium supplements, but calcium-rich foods are OK. Calcium in the food you eat does not increase your risk of getting kidney stones. Keep eating calcium-rich foods unless your doctor advises you otherwise. However, calcium supplements have been linked to higher risk of kidney stones. Consult your physician before starting a calcium supplement.
A dietitian like Nastaran can help those at risk to plan meals that will reduce the chance of getting kidney stones.