Wednesday, March 23, 2016

Your 2015 Dietary Guidelines Primer

Since 1980, the Dietary Guidelines Americans (DGA) have been published every five years, so right on cue were the 2015 DGA released in January.  According to the DGA, about half of all American adults have one or more preventable, diet-related chronic diseases, including cardiovascular disease, type 2 diabetes, and obesity. Although infectious diseases have practically vanished in the U.S., there is no end in site for chronic disease – which are mainly related to poor diet quality and inactivity. So let’s get down to the bottom line. What’s the difference between these DGA from the previous and is it really going to help Americans?

First, to understand the future of the DGA we must first look at the past. Previously, the DGA focused on nutrients in isolation and dietary food groups but people don’t consume nutrients in isolation. So the 2015 DGA focus more on healthy eating patterns over the lifetime and making ‘shifts’ to consume healthier food options. For example, shifting from white bread to 100% whole grain bread, from coconut oil (solid fat) to olive oil. I’m sure I won’t completely blindside anyone when I say that the current eating patterns of Americans don’t align with the recommendations of the DGA. Three-fourths of the population has an eating pattern low in fruits, vegetables, dairy, and oils. Roughly 70% of Americans exceed the recommended added sugar and saturated fat intake per day (<10% of calories/day) and 89% exceed the recommend sodium intake (2,300 mg healthy individuals, 1,500 mg hypertension or prehypertension).  Again, most of us probably aren’t surprised by these statistics. Let’s take a closer look at the major updates in the 2015 DGA – cholesterol, the Mediterranean/vegetarian diet, and sodium.

In 1980, emerging research implicated dietary and serum cholesterol in the development of heart disease and cholesterol became the nutrient that everybody loved to hate. More recent research suggests that cholesterol-rich foods (such as eggs) don’t actually increase serum cholesterol levels like previously thought. So the 2015 DGA Advisory Committee did something that they have never done in the past. They removed the restriction of 300 mg of cholesterol per day. Now, the DGA make it clear, it is not recommending you go out and eat all the cholesterol you possibly can since they restricted you all these years. The DGA are simply stating that there is no adequate evidenced for a quantitative limit for dietary cholesterol at this time.  A recent article published in the Food & Nutrition Magazine, titled The Cholesterol Conundrum, stated that the key to understanding LDL cholesterol’s risk and reward may lie in the size and density of its particles which range from large, buoyant, cholesterol-rich particles, to small, dense particles low in lipids.

In 2010, the DGA mentioned the Mediterranean diet but the 2015 DGA took it a step further and created a healthy Mediterranean-style eating pattern, recommending amounts of food from each food group at 12-calorie levels. Similar, the DGA created a 12-calorie level for the vegetarian-style of healthy eating. It should be noted that the healthy vegetarian-eating pattern was created based on self-identified vegetarians and therefore, includes eggs and dairy because the overall consensus of vegetarians was that the majority consume these foods.

There seemed to be a lot of disappointment around a topic that the 2015 DGA did not address, the sodium debate. While there is no dispute on restricting 1.5 grams (1,500 mg) of sodium for those individuals with prehypertension or hypertension, some research has shown that restricting sodium too much can have adverse side effects on healthy individuals. Some health professionals say that there is no health benefit to consuming less than 2,500mg per day, while the American Heart Association still sticks by the 1,500mg sodium limit for all individuals. Clearly, more research is needed to understand the affects of dietary sodium and whether we should be restricting or liberating sodium.

What can we expect for the 2020 DGA? After all, it is only five short years away. The 2015 DGA state that they plan on expanding the DGA to include toddlers and infants, as well as providing additional guidance for pregnant women. In my opinion, I think that cholesterol will be returning into the picture. Not necessarily saying that there will be a quantitative limit for cholesterol but rather focusing more on the cholesterol particle in the development of heart disease. Also, I expect dietary sodium recommendation to remain stagnant or liberated for healthy individuals.


For more information on the 2015 Dietary Guidelines visit http://health.gov/dietaryguidelines/2015/.

Alli Bokenkotter is a University of Cincinnati Dietetic Intern.  She is also the diversity and National Nutrition Month Chair of the Greater Cincinnati Dietetic Association.