Religious restrictions considered elsewhere.
Be wary of taste
Stomach over brain over tongue
Taste was evolved to identify nutrient rich food; but in the modern world, the tongue is easily fooled by cleverly mixed chemicals. In this high calorie environment, it is not wise to trust whims of the tongue.
But, that said, the autonomous ganglion in stomach needs to be satisfied.
Avoid Adverse reaction
Mild
Beware of food which cause flatulance or diarrhoea or gastro-intestinal irritation (see health info for a list of known malefactors).
Chronic danger
Malnutrients considered elsewhere should be avoided.
Organic food
Organic fruits are usually grown without the use of pesticides. In the case of apples, the difference in taste was apparent, and the white deposits near the stalk was absent.
Apples/ peaches etc, berries, grapes are especially vulnerable to high pesticide use. Beware of organic produce which claim to use organic pesticides - they tend to be deadlier than inordganic pesticides!
Low glycemic index food
Avoid high glycemic index food in order to stay satiated for longer.
Prefer intake of food with high portions of soluble fiber. Note that this is different from food high in insoluble fibers. [Ref] .
Fats tend to ensure longer satiety too.