Every five years the government assigns a group of experts to scour the latest scientific evidence to help form the Dietary Guidelines for Americans. These experts convened in Washington , DC last week and the meeting was made public via a webinar. This was the fourth meeting of the Dietary Guidelines Advisory Committee. I wrote about the previous meetings in posts titled Debating Our Diets and What Should Americans Eat.
The recommendations are expected to be finalized in late spring or early summer. Then they’ll be translated into an updated food pyramid and will guide policymakers, nutrition educators, school lunch professionals and health providers. So they’re a big deal.
It’s hard to say where the committee will end up, but here are some of the major points that I took away from the two-day meeting.
- Obesity is public health enemy number one. No surprise, the group spent a lot of time talking about the country’s obesity epidemic. They reviewed the latest evidence and basically concluded that…it’s the calories, stupid. It’s not about manipulating carbs, fats or protein. The impact of the glycemic index and glycemic load was also dismissed. It all comes down to total calories and dietary patterns.
- Spend your calories wisely. The concept of nutrient density or eating more nutrient-rich foods was widely embraced. That means eating foods that are rich in nutrients yet contain the lowest calories as possible. It’s about considering “nutrients per calorie” or getting the biggest nutritional bang for your calorie buck. To illustrate this concept, the committee reviewed a dietary model or a theoretical calculation that showed if someone followed the guidelines but ate foods at the higher end of fat and sugar, they would consume 2,400 calories. If someone chose the same types of foods but selected more nutrient-rich options that were lower in fat and sugar (such as fat free milk instead of whole, or broth-based soups instead of creamy) they would consume 2,000 calories. This is a “gap” of 400 calories between the “typical” and the “ideal.” It’s where we need to move people to help them lower total calories but maximize nutrient intake.
- Nutrients of concern. Even with our widening waistlines, we’re still falling short of several essential nutrients. It’s like we’re overfed, but undernourished. The importance of eating nutrient-rich foods was underscored by research presented on the nutritional inadequacies in the American diet. The “nutrients of concern” for children and adults are calcium, vitamin D, magnesium, potassium and dietary fiber. For specific population groups, including seniors and women of childbearing age, the shortfall nutrients include vitamin B-12, folate, choline, iron and phosphorus.
- Praise for a plant-based diet. The committee spent a lot of time discussing the merits of a more plant-based diet. In fact, the group received a flood of public comments (most of the 750 comments submitted) about vegetarian/vegan eating. While I don’t think we’ll see the Dietary Guidelines actually recommend a meat-free diet, I do expect there will be a greater emphasis on plant-based foods. The committee said it’s important that Americans shift to a diet with fewer animal-based foods to a diet more focused on plant foods. One committee member hoped Americans would begin eating meat 2-3 times per week instead of 2-3 times per day. Expect to see the flexitarian approach gain even wider recognition.
- Variety of vegetables. There was a lot of talk about realigning vegetable subgroups. Currently there are 5 subgroups: dark green, orange, starchy (potatoes) legumes (beans) and other. The committee discussed ways to better categorize vegetables, including defining “other” and adding a red/orange group that includes tomatoes (since tomatoes are a big contributor to overall vegetable intake). They also talked about ways to reinforce the importance of eating a wide variety of vegetables, including the concept of choosing the deeper, darker ones most often — such as kale instead of iceberg lettuce.
- Cut the salt. All eyes are on sodium as the next dietary evil. In fact, sodium may be the new “trans fat.” We now consume an average of 3,400 mg of sodium per day, yet we should keep our intake to less than 2,300 mg per day. There’s been a lot of speculation about lowering daily sodium recommendations, but the group said it’s going to be tough for Americans to eat less sodium because of the current food supply. That’s why they discussed the goal of incrementally reducing sodium from 2,300 mg to 1,500 mg in a stepwise fashion. They also talked about linking sodium to calories instead of the same blanket recommendations for everyone. That means people with higher calorie needs would have a slightly higher upper limit of sodium compared to those with lower calorie needs. This concept of anchoring specific nutrient intake levels to calories was a frequent theme (including fiber recommendations).
Two more meetings are planned before the release of the scientific report in late spring or early summer 2010. I’ll keep you posted. Sure, it’s easy to be cynical about the government guidelines and question if the average joe consumer is even aware of them. But at least there is a systematic, evidence-based process of evaluating scientific research. The guidelines are not simply a point of view — they’re based on peer-reviewed research. So I can certainly support that.