When it comes to fruits and vegetables, it’s not only quality and quantity that counts, but also variety. We know, for example, spinach is healthier than lettuce (see #1 Anticancer Vegetable for a comparison of salad greens), and a big salad is better than small, but is it better to get the spring greens mesclun mix than the straight spinach? Is it healthier to eat one apple and one orange than it is to eat three apples or three oranges?
I think we’re used to some of the more generic plant compounds like vitamin C, which is found scattered throughout the plant kingdom, but there are other specific phytonutrients produced by specific plants to perform specific functions—both in their organs and ours. We miss out on these if we’re stuck in a fruit and vegetable rut, even if we’re eating a lot every day.
There are tens of thousands of these phytonutrients (see my 2-min. Phytochemicals: The Nutrition Facts Missing From the Label), but they’re not evenly distributed throughout the plant kingdom. For example, those wonderful glucosinolates, which I discuss in The Best Detox, Broccoli Versus Breast Cancer Stem Cells, and Lung Cancer Metastases and Broccoli, are found almost exclusively in the cabbage family. Likewise, you won’t get lemonoids like lemonin and limonol or tangeretin in apples. Comparing apples and oranges is like, well, comparing apples and oranges.
At the same time, all fruits are just fruits, whereas vegetables can be any other part of the plant. Roots harbor different nutrients than shoots. Carrots are roots, celery and rhubarb are stems, dark green leafies are leaves of course, peas are pods, and cauliflower is true to its name as a collection of flower buds, but all fruits are just fruits. The available evidence suggests it may be most important to get in a variety of vegetables so you can benefit from all the different parts of the plant. An interesting pair of studies was released recently that looked at disease risk and the variety of fruit and vegetable consumption, which I detail in today’s NutritionFacts.org video pick above.
In terms of fruit and vegetable quality, berries are the healthiest fruits (see Best Berries) and greens are the Healthiest Vegetables. For more on the anti-inflammatory nature of plant foods, see my 1 min. video Anti-Inflammatory Antioxidants and my 2 min. Aspirin Levels in Plant Foods.
Michael Greger, M.D.
Image credit: kharied / Flickr