Study: It Does Not Have to Be Plant Vs. Animal

  • Article
  • July 15, 2016

Which eating style is both healthy and good for the environment? It’s a question that is being asked more frequently. Some believe that eating plans rich in plant-based foods and with minimal animal-based foods are not only best for health, but also necessary to lower greenhouse gas emissions and meet certain climate targets. However, there is not enough research to date to make this conclusion, and the opposite may be true.

It has long been accepted that fruits, vegetables, whole grains and legumes are important components of healthy eating plans. And, animal-based foods, such as milk, cheese and yogurt, also are components of healthy eating styles as they contain high-quality protein and are major contributors of essential nutrients to the American diet, including many vitamins and minerals. What is less clear is what could happen if people eat more plant-based foods in lieu of animal-based foods without meaningful behavior change to current eating styles. Americans currently do not meet recommendations for plant-based foods, so asking them to eat more of them may present a behavioral challenge. A new study looked to answer that question.

National survey data was used to model three different eating scenarios that increased the consumption of:

  1. Plant-based foods as currently consumed
  2. Protein-rich plant-based foods (i.e., legumes, nuts, seeds, soy)
  3. Milk, cheese and yogurt

The first two scenarios had equal reductions in animal-based foods consumption to mimic what has been suggested by some to improve health and the environment.

The results showed that increasing certain foods (and for the plant-based food models, proportionately decreasing animal-based foods) within current consumption patterns directly affected nutrient adequacy. Compared to current consumption, increasing plant-based foods resulted in improved consumption of key nutrients like iron, vitamin E and folate, but also resulted in an increase of individuals not meeting the estimated average requirement for vitamin A and two nutrients specified in the 2015 Dietary Guidelines for Americans as nutrients of public health concern: calcium and vitamin D. Interestingly, doubling consumption of high-protein plant-based foods had little effect on nutrient adequacy in this study. This is mainly due to the current low consumption of these foods in the U.S., suggesting that substantial behavior change would be needed to get people to eat more legumes, soy and other protein-rich plant-based foods to help meet their nutrient needs in the absence of animal foods. Finally, compared to current consumption, increasing dairy foods increased consumption of energy, saturated fat and sodium, but also improved the mean consumption of vitamin A, vitamin D, magnesium and calcium in both children and adults.

So, which eating style is both healthy and good for the environment? The question is still difficult to answer. Nutrition and environmental science are two complex disciplines, and they cannot really be separated as we move forward to improve the health of people and the planet. But, this study does provide additional clues, especially if we keep health top of mind. Mainly that well-balanced, healthy eating styles, that contain a mix of dairy foods and healthy plant-based foods, can help close the nutrient gaps that exist among Americans of all ages.