Many people equate vegetarian eating with healthfulness. But just how much do vegetarian diets affect people’s health?
This past week, I attended the International Congress on Vegetarian Nutrition, a conference exploring the research on vegetarian diets and health, including aging, obesity, cancer, type 2 diabetes and other chronic diseases.
We enjoyed a lot of lively discussion on these topics – both areas of agreement and those that are controversial. Here are a few of my take-aways from the conference:
1. Our overall diet – what we eat day in and day out – is what counts, not just nutrients. But a plant-based diet IS most healthful.
One of the most consistent findings in epidemiological studies is that a plant-based diet (at least 2/3 of your plant filled with plant foods, 1/3 or less from animals) is the best way to promote health and prevent chronic disease. But focusing on any one food or nutrient as a cause or cure of our health problems is misplaced. Food, not nutrients, is the fundamental unit in nutrition.
The principal investigator of one of largest European studies on cancer reported that people following AICR/WCRF’s recommendations for cancer prevention have lower rates of several cancers, including breast, endometrial, esophageal and liver. AICR does promote a plant-based diet – the New American Plate, along with recommendations to be physically active and be a healthy weight.
2. Being a vegetarian doesn’t necessarily mean your healthy.
People follow a vegetarian or vegan diet for many reasons, but health is not always one of them. If you just remove meat or animal products from your diet it doesn’t automatically make it healthy.
For example, vegetarians and vegans typically have lower bone mineral density and a higher risk for bone fracture than do omnivores. Eating a plant-centered diet does mean getting more of some nutrients that help strengthen bones, such as vitamin C, magnesium and carotenoids – often lacking in the typical American diet. But vegans and vegetarians are often low in other key bone nutrients like calcium, vitamin D, and even total protein. Knowing how to get these nutrients by consuming a variety of legumes, leafy greens and possibly, vitamin D fortified foods in a plant-centered diet is crucial to bone health.
3. Topics like the role of dairy and omega-3 fatty acids in our health are controversial and not completely understood.
Dairy’s effect on cancer is mixed. AICR’s expert report and its updates found that milk is probably protective for colorectal cancer, but diets high in calcium may increase risk for prostate cancer. On the other hand in one presentation we learned that milk drinkers have a 16% lower risk for type 2 diabetes than non-milk drinkers.
We hear a lot about omega-3 fats and their link to heart disease and other health concerns, but what are the differences between the plant and animal sources? Can vegetarians rely on plant sources that are rich in the omega-3 fatty acids – like walnuts or flaxseed – or is fish the only way to get enough?
4. A Plant-Based Diet: Not Just Healthful – Also Delicious!
Even though we don’t know the answers to all these questions, there was unanimous support for eating a colorful and varied plant-based diet. And agreement that if Americans would make even modest changes to include more vegetables, fruit, whole grains, legumes and nuts in our diet we’d see lower rates of cancer and other chronic diseases. Finally, no controversy on the vegan lunches; they were very tasty – wraps with sweet potatoes and greens, and perfectly seasoned quinoa and red pepper salad for example.