The 2015 report by the Dietary Guidelines Advisory Committee (DGAC) features a new section on sustainable diets. The average American diet has a larger environmental impact in terms of increased greenhouse gas emissions, land use, water use, and energy use than other plant-based dietary eating patterns. Several countries like Germany, Sweden and other Nordic countries, the Netherlands, Australia, and Brazil already include environmentally-sustainable dietary guidance in their nutrition recommendations. The DGAC report includes elements of these guidelines, recommending a focus on decreasing meat consumption, choosing seafood from non-threatened stocks, eating more plants and plant-based foods, reducing calorie intake, and reducing waste.
A major finding from the 2015 DGAC report is that a diet that is higher in plant-based foods and lower in calories and animal-based foods promotes health and is associated with less negative environmental impact than the current U.S. diet. No food groups need to be completely eliminated to improve the sustainability of our food choices, and shifting from less animal foods to more plant foods is recommended. Consider moving from an animal-based to a plant-based diet. Learning not only about what we eat, but also about where and how food production, processing, transportation, and waste are managed is crucial to ensuring a sustainable food supply.
The guidelines include several nutrients of concern for underconsumption, including vitamin A, vitamin D, vitamin E, vitamin C, folate, calcium, magnesium, and fiber. A plant-based diet can meet the recommendations for all of these nutrients.
- Calcium: While the majority of dietary calcium is obtained from milk and milk products, fortified juice and some soy products and vegetables also contribute significant amounts of calcium. However, the calcium bioavailability from plants is lower than from dairy products.
- Vitamin D: Vitamin D can be obtained from the diet by consuming fluid milk and some milk and yogurt products, fortified juices, fortified breakfast cereals, and some fortified grain products. The DGAC recognizes that some people may benefit from vitamin D supplementation.
- Fiber: Because the current average intake of fiber is at half the recommended levels, an emphasis on including high-fiber cereals and whole grains, and meeting recommendations for vegetable and fruit intake is encouraged.
Dairy products contain several nutrients of concern, including vitamin D, calcium, and potassium. When people consume no dairy products, levels of calcium, magnesium, iron, vitamin A, and riboflavin drop below 100% of goals, and levels of potassium, vitamin D, and choline also drop significantly.
However, for people who follow a vegetarian diet, who do not tolerate dairy, or who prefer to avoid dairy, fortified soymilk and other plant-based milk-type products such as almond or rice milk can be used to provide calcium and magnesium, although the absorption of calcium is less efficient from plant-based beverages. Know that the levels of vitamin D and potassium in plant-based dairy alternatives can vary significantly, and calorie levels are often higher in these products.
Protein is found in a broad group of both animal and plant-based foods, giving consumers a range of choices to meet protein needs. Protein foods are also an important source of iron, which is under-consumed by adolescent and adult females and is especially important for young children and pregnant women. Animal proteins provide heme iron, which is more bioavailable than the non-heme iron found in plants. Select a variety of iron-containing foods to meet your individual needs.
The DGAC recommends three additional areas of research on fat intake, blood lipids, and CVD risk:
- Examine the potential benefits of substituting monounsaturated fatty acids from plant sources for saturated fat on CVD risk.
- Examine the effects of saturated fat from different sources, including animal products such as butter and lard, as well as plant products such as palm and coconut oils.
- Examine the effects of various production systems, such as refined, deodorized, and bleached coconut oil vs. virgin coconut oil.
And there you have it! A comprehensive review of the plant messages from the DGAC!
By Lynn Grieger, RDN, CDE, CPT, CWC
Stephanie Ronco has been editing for Food and Health Communications since 2011. She graduated from Colorado College magna cum laude with distinction in Comparative Literature. She was elected a member of Phi Beta Kappa in 2008.