TCM groups food in 5 thermal categories: hot, warm, neutral, cool, and warm.  Depending on your constitution, you want to eat food that's appropriate and beneficial for your constitution.  In general, neutral foods are universally accepted and appropriate to consume for all constitutions.

Below are examples of neutral foods:

Vegetables
Squashes, mushrooms, cabbage, corn, broccoli, potato, sweet potato, taro, bok choy, spinach, beet root, brussels sprouts, carrots, cauliflower, fennel bulb, green beans, parsnip, rutabaga, turnip, eggplant.

Fruit
Figs, cherries, grapes, plums, apricot, goji berries.

Grains/Seeds
Rice, oats, buckwheat, barley, rye, tofu, azuki beans, kidney beans, pinto beans, white beans, almond, walnuts, sesame seeds, sunflower seeds, soy beans, hemp seeds, black eye peas

Meat
Pork, beef, buffalo, venison, duck, squab, chicken eggs, quail eggs, fresh tuna, perch fish, bass.

Herbs
Basil, Thyme, Chrysanthemum flowers (Ju Hua), Tremella Mushroom (Bai Mu Er), Reishi Mushroom (Ling Zhi), Poria Mushroom (Fu Ling), Mountain Yam (Shan Yao), Solomen’s Seal (Yu Zhu), Burdock Root (Niu Bang Teng), Goji Berries (Gou Qi Zi), Licorice Root (Gan Cao), Lotus Seeds (Lian Zi), Codonopsis (Dang Shen), Siberian Solomon’s Seal (Huang Jing), Polygonum Vine (Ye Jiao Teng).

Condiments
Camellia Seed oil, Safflower Oil, Sunflower Oil, Sesame Seed Oil (light), Light Soy Sauce.