While walking through the grocery store during a shopping trip over this recent Thanksgiving break, I noticed that one particular item has nearly taken over the dairy isle – yogurt. It’s becoming increasingly difficult to find other traditional dairy products amid the abundant selection of yogurt products. This led me to research some of the health benefits of this increasingly popular food. My findings were intriguing. A recent study conducted by the Harvard School of Public Health reveals a potential link between higher consumption of yogurt and a reduced risk of type 2 diabetes.
Over 29 million people or 9.3% of the U.S. population have been diagnosed with diabetes according to recent reports from the government’s Centers for Disease Control and Prevention. For many of those people, the obesity factor increased their risk significantly for developing the disease. In fact, four out of five people with type 2 diabetes are overweight or obese.
One problem is that excess fat changes the way that a person’s body responds to insulin -the hormone that allows glucose (sugar) to leave the bloodstream and enter the cells to be used as fuel. Type 2 diabetes occurs when the pancreas doesn’t make enough insulin, or the cells of the body become resistant to insulin. Additionally, as Vivian Fonseca, professor of medicine and pharmacology and chief of endocrinology at Tulane University Health Sciences Center, asserts, “One of the links with obesity is that fat induces a mild, low grade inflammation throughout the body that contributes to heart-disease and diabetes.”
However, people with diabetes can control their blood glucose by following a program that includes regular physical activity, a healthy eating plan, and medication. Education on diet and self-care practices is a critical aspect of controlling diabetes and staying healthy. In light of modern research, it might be beneficial for those striving to prevent diabetes to weigh the costs and benefits of adding a daily serving of yogurt to their diet.
The HSPH observational study utilized a large sample size of adults, tracking the progress of 3 studies: 41,436 men in the Health Professionals Follow-Up Study (1986 to 2010), 67,138 women in the Nurses’ Health Study (1980 to 2010) and 85,884 women in the Nurses’ Health Study II (1991 to 2009). In 1980, NHS participants were administered a 61 question food frequency questionnaire in order to collect information on their usual intake of foods and beverages. Every two years after, these participants completed a similar yet expanded 131 question FFQ to update their diet records. A similar procedure was conducted in the NHS II and Health Professionals studies.
Throughout the course of the investigation, researchers documented 15,156 cases of diabetes. They conducted a further analysis of individual types of dairy products and their associations with risk of type 2 diabetes. Surprisingly, the researchers found little correlation between general dairy intake and diabetes. However, greater levels of yogurt intake were significantly associated with a lower risk of type 2 diabetes. The study concluded that a daily increase of one yogurt serving was significantly associated with an 18% reduced risk of developing diabetes.
Because of the observational nature of the study, the associations do not definitively indicate causation. Those who eat yogurt frequently may just have a healthy lifestyle and thus be at less risk. It is also possible that yogurt consumption has a positive correlation with other indicators of a wellness, such as exercise or a healthy diet.
When critiquing this research, it is important not to rule out reverse causation as a potential factor. Some overweight participants and possible diabetics may have tried to incorporate yogurt into their diet as an effort to improve health. Thus, diabetes risk could cause people to increase their yogurt consumption. Even in a study that attempts to control for these factors, chance is always a possibility. Also, because the response-based survey method was used in all three investigations, some error measurement of dairy intake assessment is unavoidable, despite researchers’ efforts to control for variation.
Additionally, since the study did not assess the types or brands of yogurt consumed, researchers cannot definitively attribute observed benefits to various components of yogurt. However, in a recent Forbes interview, Frank Hu, the study’s lead author and researcher, stated, “One hypothesis is that the probiotics in yogurt may help to improve insulin sensitivity and reduce inflammation, but this hypothesis needs to be tested in randomized clinical trials.” Perhaps further research will yield more information on the separate components of yogurt and their different affects on metabolic health.
Overall, eating a daily serving of yogurt is a relatively low cost action that has the potential to yield highly favorable health benefits. However, before immediately adding it to your diet as a means to decrease your chances of getting diabetes, it is important to consider a variety of factors. One should review the financial and opportunity costs that come with buying the product. As long as yogurt consumption isn’t used as a means to replace other healthy habits such as exercising and maintaining a balanced diet, it may not be a bad idea to add it to your diet. Even if you’re not at risk for diabetes, chances are it could play a small role in improving your health.