Dr. Weil doesn't seem to have a page for "What to do if this diet is too restrictive for me." Leaving aside the scientific rationale or lack thereof behind this pyramid, not everyone can stomach soy products, tolerate legumes, or afford that many vegetables.
Suitability for athletes and others with high calorie needs
Dr. Weil's diet, like most so-called anti-inflammatory diets, is based around low-calorie foods. I've crunched the numbers and found that, using the larger recommended portion sizes, his daily diet consists of about 500 calories of whole grains, 300 calories each of beans and soy, 300 calories of plant fats, and 200 calories of fish, plus fruits and veggies. Total calorie intake would be perhaps 1,500 to 2,000 calories daily, sufficient to meet the needs of those who are trying to lose weight, but not necessarily enough for active, larger adults who are trying to maintain or gain weight. The low calorie density of recommended foods might make it hard for some people to eat sufficient amonts of food to meet their calorie needs.
Suitability for those with eating disorders or disordered eating patterns
Dr. Weil's site is filled with catchphrases like "head to toe wellness," but a quick search of his website for orthorexia revealed some disturbing news. In the article, he weasled his way out of giving a straight answer as to whether his diet could promote obsessive eating by saying that orthorexia has not been recognized an official mental illness. He added that he occasionally consumed treats like pizza and chocolate. The fact that these foods are allowed at most once a week on the Weil diet--and that he recommends eating them as little as possible--does not seem to concern him.
Speaking as someone who used to look up the nutritional facts of every food before eating it, and who once adopted extreme low-carb dieting with disasterous consequences, I can say for sure that orthorexia exists. Extreme diets like the Weil diet are not the solution to eating disorders or disordered eating. If you suspect that you are suffering from either of those illnesses, please seek medical help immediately.
Back to supplements. I suspect that Dr. Weil recommends them mostly so he can make money from sales of the absurdly overpriced "natural" "food-based" supplements sold on his website. Some of his supplements cost $60 or more for a month's worth. His exact words:
How much: Daily
Healthy choices: High quality multivitamin/multimineral that includes key antioxidants (vitamin C, vitamin E, mixed carotenoids, and selenium); co-enzyme Q10; 2-3 grams of a molecularly distilled fish oil; 2,000 IU of vitamin D3
Why: Supplements help fill any gaps in your diet when you are unable to get your daily requirement of micronutrients.
Dr. Weil says the supplements are to fill gaps in the diet. If his diet is so perfect, one wonders why there are so many gaps. Allow me to evaluate each supplement individually:
On 7+ servings of produce daily, the chances of vitamin C insufficiency are next to none.
Tree nuts, veggies, whole grains, and flax are stuffed with vitamin E, so no problem there.
Carotenoids (a class of compounds including beta-carotene, the precursor to vitamin A)
Colorful veggies are chock-full of carotenoids, and supplemental beta-carotene can be harmful.
Seafood is extremely rich in selenium and Dr. Weil recommends a boatload. It's true that shellfish (oysters, mussels, shrimp, etc.) tends to be higher in selenium than finfish, but one could eat shellfish rather than supplements.
CoQ10 is abundant in beef heart, but that's an evil red meat and must be avoided at all costs. Luckily, oily fish is also rich in the antioxidant, so there should be no need for supplements.
At 1/2 to 2 lbs of oily fish a week, the chances of an omega-3 deficiency are next to none. There are concerns that an excess of omega-3 might contribute to angiogenesis and malignant tumor development, which is plenty of a reason to skip the extra fish oil.
Vitamin D is good to take in the event of insufficient sun exposure, but I would recommend buying it from Nature Made. Nature Made supplements are vetted by an independent organization to contain the stated amount of the active ingredient and to be free of heavy metals and other contaminants. Dr. Weil's supplements are not, to my knowledge, independently vetted.
I am currently working on a review of The Abascal Diet, another anti-inflammatory diet. I'm not sure which I like less, the Weil diet or the Abascal diet. I haven't investigated Dr. Weil well enough to know if he has committed any gross errors of basic biology and chemistry, like Ms. Abascal, who is allegedly a biochemist. However, Ms. Abascal's approach is much more flexible and therefore has less potential to cause harm.