In the news: Gluten-Free Diet Shortfalls; “Multi” Use Linked to Better Heart Health

Gluten-Free? Watch Out for Nutrient Shortfalls

Gluten is a protein found in grains such as wheat, barley, rye and triticale (a cross between wheat and rye). People with celiac disease or allergy to wheat protein have to avoid gluten-containing foods because they trigger an autoimmune or allergic response that inflames and damages the small intestines.

But eliminating gluten from the diet has also become increasingly popular among non-celiac, “gluten-sensitive” individuals who identify digestive, mood, and energy symptoms with consuming this protein.

How do gluten-free diets stack up against non-gluten free diets in terms of balanced nutrition? To evaluate the nutritional quality of these diets, researchers reviewed published studies on that diet over the last 25 years (1). For one thing, they found gluten-free diets to be poor in fiber – no surprise because of the necessary avoidance of fiber-rich grains.

The gluten-free diet also was found to have a higher glycemic load compared with non-gluten free diets. Diets with a higher glycemic load can increase blood sugar levels more rapidly, and may lead to weight gain. Many products free of gluten are made from refined flour and starch. When grain is processed to remove gluten, the outer fiber-containing layer is removed leaving starchy, sugary flour with a higher glycemic index.

Additionally, gluten-free eating patterns were seen to be higher in saturated fats and calories compared to non-gluten free diets.

In terms of vitamins, the most common deficiencies were B12, D, and folic acid. Calcium, magnesium, iron and zinc topped the list for common mineral shortages.

So what strategies can improve the quality of gluten-free diets? Choose and prepare gluten-free grains and limit your intake of processed gluten-free products. Grains that don’t contain gluten include quinoa, buckwheat (kasha), amaranth, rice (brown or white), millet, soy and corn (meal, flour, grits, etc). Read product labels to avoid high saturated fat content, and consider taking a daily multi-nutrient supplement to help close potential vitamin and mineral gaps.

Can Long-Term Multi Use Lower CVD Risk?

That question prompted Harvard researchers to examine whether taking a daily multivitamin/mineral supplement over the long haul is associated with the risk of cardiovascular disease (CVD) in healthy men.

The investigators studied 18,530 male physicians from the Physicians’ Healthy Study I, who were free of CVD at the study’s start (2). The participants provided clinical, lifestyle, and dietary information including their use of dietary supplements, and were followed for just over 12 years on average.

While there was only a relatively weak association between multi use and heart benefits in the shorter term, longer use – for 20 or more years – was associated with a 44% lower risk for major CVD events including heart attack, stroke and death from CVD. Multi use was also linked to a lower risk of ischemic reperfusion injury. This injury happens after a shortage of blood and oxygen to the heart resolves. The high oxygen flowing back in triggers inflammation and more damage.

Since supplement users are generally more health-conscious than non-users, it’s possible that the observed CVD risk reduction simply reflects healthier behavior. However, CVD develops over a long period of time, and various vitamin and minerals have been shown to protect LDL cholesterol from oxidation, promote the arteries’ ability to dilate when needed, and to bolster homocysteine metabolism – mechanisms that may well contribute to CVD prevention over time. The authors also note that several other observational studies have also reported cardiovascular benefits among long-term multi users.

References:

1. Vici G, et al. Gluten free diet and nutrient deficiencies: A review. Clin Nutr. May 7, 2016 [Epub ahead of print].
2. Rautiainen S, et al. Multivitamin use and the risk of cardiovascular disease in men. J Nutr. 46:1235-240, 2016.