I don’t necessarily think vegetarianism is a bad diet, particularly if the alternative is the kind of diet that a typical american actually eats. There is a lot of evidence that–compared to the average american–vegetarians have lower mortality and rates of disease from most metabolic disorders.
On the other hand, causality is difficult to decipher. Vegetarians are probably more likely than average to actually like vegetables. So…are they healthy because they DON’T eat meat, or because they DO eat veggies? It is hard to know. They’re probably also more likely than average to take care of themselves in other ways, such as maintaining a healthy weight and exercising.
I wouldn’t worry a lot about protein needs, unless they are athletes. I think human protein needs are very much an open question. There is some research on macronutrient profiles that seems to show that high protein dieters have better cholesterol and blood pressure numbers than high carb dieters, however there is also research showing not much effect. My best guess is that most people in first-world countries are not in danger of a protein deficiency. If they’re eating beans and nuts they’re probably fine.
My concerns with a vegetarian diet would be twofold:
- essential fatty acids. If you don’t eat fish, it’s probably wise to supplement with fish oil or at least flax oil. The health benefits of fish are legion. Also, including low fat dairy products is a good way to get protein and potassium in a diet otherwise high in plant foods.
- sugary, starchy carbs. Being vegetarian alone does not make something healthy. If you eat lots of sugar, and potatoes and processed bread, you’ll still get fat and have high high cholestrol even if there are no animal products in there. I think you DO have to watch what kind of carbohydrates you eat, even if you’re a vegetarian. It’s not a license to pig out on Wonderbread. I would worry that vegetarian who wasn’t eating much protein or fat from animal sources would make up the discrepancy by eating things like bread and potatoes, which is not a net benefit.
Here are some good books that have influenced my thinking on nutrition, that you might recommend to them.
- The Paleo Diet – Loren Cordain
- Eating Well for Optimum Health – Andrew Weil
- The Protein Power Diet – M&MD Eades
- The Omega Diet – a greek author whose name I don’t remember. Artemis something.
I also tend to like most of what I hear from John Berardi on this site. Although I haven’t read his books, I plan to. He makes sensible recommendations like eating complete protein and veggies with every meal, and consuming carbs at times of high insulin-sensistivity, like early in the morning or immediately following workouts. His Seven Habits of Highly Effective nutrion programs is a good article.
I’m not an expert by any means, I’m just a guy with a family history of things like heart disease and stroke, who has spent a lot of time reading about nutrition to try and assess what a healthy diet should look like. Probably others on this site know a lot more than I do.
I’ve simply tried to read what’s out there and look for the common threads that experts tend to agree on.
The only really firm position I have is that people who advocate excessive carbohydrate consumption are wrong. The evidence on this point has gotten so increasingly clear over the last 10 years, I don’t understand why there is still so much support for a grain based diet.
Here are the rules I eat by. Not saying that they are right, just saying that they are my best guess at present
- Lots of fruits and veggies
- Lots of fish and lean poultry
- Liberal use of olive oil and flax oil
- Nuts, berries, and nut butters
- Occasional soy
- Occasional oatmeal or sprouted grain breads
Things I try to avoid:
processed breads, pasta, sweets, potatoes, white rice, fatty cuts of meat, vegetable oils, any hydrogenated fats, corn syrup, and any other ingredient I don’t recognize as coming directly from a plant or animal.
I would encourage them to add fish and yogurt, and I wouldn’t worry too much about the rest of their diet unless they’re pigging out on the fettucine.
I think black coffee and red wine are not harmful in moderation.