By Lauren M. Koch, RDN
I was just recently asked this by a client. Those exact words. So it got me thinking; Maybe the answer is not as obvious as I thought. Do you really need vegetables in your diet? Well, let us go through a few things, then you can decide.
I can’t say that it’s uncommon to have a client complain about eating vegetables. Poor veggies tend to get a bad rep somewhere along the way. Personally, I don’t remember if I ever gave my mom a tough time about eating the green stuff (Though I feel quite sure I didn’t). I have had my share of frustrations with my own kids. But compared to stories I hear in the mommysphere, they are veggie-eating angels.
It’s kind of strange right? Most of us start out eating almost primarily fruits and vegetables as infants. I mean, your first food was most likely peas, carrots, or some other squishy and nutritious vegetable. So why all the hate later in life?
Anatomy of a Vegetable
To understand why veggies are so important, we need to talk about what is in them. As with most living things, the vast majority of their insides is water. On average, somewhere in the mid 90% by weight. Other than that, you’ve got fiber, sometimes a tiny bit of sugar, and micronutrients (vitamins, minerals, and other phytochemicals). This is where vegetables differ from fruit, nutritionally speaking. While still very nutritious, fruit is more calorie-dense with over three quarters of its calories coming from sugar. And some is even higher. Cantaloupe, for example, yields a whopping 96% of its calories from sugar.
To convince you to welcome vegetables into your daily routine, let us discuss the roles of each of these components in the body.
Why we need fiber
Humans are actually incapable of digesting fiber, and it provides us zero in the way of nutritional value. So why do we need it?
It may not nourish us, but it does feed our gut, so to speak. Beneficial bacterial strain like lactobacillus and bifidobacterium rely on us to eat fiber-rich foods to stay healthy. Otherwise, pathogenic bacteria like E. Coli, and C. difficile, as well as yeast can grow out of control. Check out my previous post on probiotics and prebiotics for more information on what they are, and where to find them.
There is also another class of fiber whose job is less glamorous (’cause feeding bacteria is pretty glamorous, no?). These are the insoluble fibers. These go in one end, and right back out the other in pretty much the same form. Their job is to maintain bulk in the stool, and keep things moving along in our system.
Based on a review of the literature, here are some of the well-documented health benefits of consuming plenty of fiber:
- Lower cholesterol levels
- Lower blood pressure
- Lower incidence of cardiovascular disease (reduced arterial stiffening)
- Lower body weight
- Improved blood sugar control
- Improved regularity
The recommended intake to achieve these benefits is 25gm per day for women, and 38gm per day for men (slightly less for those over 51 years of age, 21gm and 30gm respectively).
Why we need micronutrients
First, what do I mean by ‘micronutrient’? This is a general term for the range of chemical compounds found in plant products. Vitamins and minerals being the most well understood. But the reality is, they are only a small snapshot of the substances that exist in plant life.
There are roughly 5000 phytochemicals that have been identified, but it’s likely that there are far more. For example, glucosinolates are a compound found in many cruciferous vegetables like cabbage, broccoli, and cauliflower. It has been suggested to activate an enzyme in humans that may prevent cancer. The flavonoid quercetin has shown promise in improving physical and mental performance and reducing infection risk.
If you are a numbers person and would like your risk quantified, recent research out of the Imperial College of London has you covered. They found that 10 portions of fruit and vegetables daily resulted in:
- 13% reduced risk of cancer
- 28% reduced risk of cardiovascular disease
- 33% reduced risk of stroke
- 24% reduced risk of heart disease
- 31% reduction in risk of premature death
We barely scratched the surface today, so brace yourself for more in the future. One last comment before I leave you today. I have clients often ask my opinion on taking vitamins to make up for a poor quality diet. Here’s the thing. Vitamins, minerals, and other food chemicals are not nearly as effective when isolated, and taken in supplemental form. They just don’t work as well when not working in conjunction with the plant as a whole. So stick to getting your nutrients from whole foods whenever possible.
Featured Image: photo by Webvilla
carrots/chard/radishes: photo by Daniel Cuklev
cabbage: photo by Arnaldo Alanda