His intelligence has increased. If you want to move towards a vegan diet, contact your national vegetarian or vegan organisation, where there will surely be some vegans to help you. Add to this some nuts and seeds. You will find that a vegan diet contains every nutrient you need including plenty of calcium and essential linoleic and linolenic fatty acids, but without the cholesterol, saturated fat, microbes, pesticides, hormones and antibiotics that you'll find in all animal products, especially cheese and eggs. Cheese has more fat than meat and comes from the same place.
Eggs have more cholesterol than chicken and come from the same place.
Neither contain any fibre, carbohydrate, or anything that you will not find much more healthily in plant foods. There is a myth that we need dairy products for calcium and protein. However there is not one single case in the medical literature of dietary calcium deficiency in a calorie sufficient diet. Only Eskimos have a higher calcium consumption, and they in fact have the very highest rate of osteoporosis. Osteoporosis is not a disease of calcium deficiency, it is a disease of calcium loss caused in older people largely by eating too much animal protein which is disposed of using calcium from the bones.