To function properly, the human body needs to maintain homeostasis, or equilibrium. It does this, in part, by maintaining pH, a measure of alkalinity and acidity in the body, also called acid-base balance. Your diet plays a major role in maintaining the acid-base balance. According to the ChiroCare website, a healthy diet contains one-third acid foods and two-thirds base foods.
Fruits and Vegetables
Most fruits and vegetables are base foods, meaning they have an alkaline effect on your body when consumed. The measure of alkalinity differs, though, with some foods being more alkaline than others. For example, bananas are more alkaline than watermelon, and celery and kale are more alkaline than mushrooms and onions. The exception in this category are lentils and peas, which have an acidic effect on the body.
Grains and Grain Products
All grains and foods made with them have an acidic effect on the body. This includes whole-meal and refined bread and pasta, white and brown rice, amaranth, millet, oats, buckwheat, spelt and rye.
Seafood and Meat
From salmon to steak, all animal flesh has an acidic effect on the body. Some of the most acidic foods in this category are shellfish, sardines, prawns, trout, goose, liver, rabbit and processed meats such as canned corned beef, lunch meat and salami.
Dairy and Eggs
With a few exceptions, milk and products made from milk are acidic. This includes whole and reduced-fat milk, cottage cheese, Camembert, Edam, Parmesan and processed cheese. Eggs are acidic, but the yolks are far more acidic than the whites. Kefir full-fat cheese is neutral, while whey, the liquid left over after milk has been curdled and strained, is base.
Fats and oils vary; butter is acidic because it's made from dairy. Margarine is base, and olive and sunflower seed oils are neutral -- meaning they have neither a base nor acidic effect on the body. Most nuts are acidic, except for hazelnuts, which are base. Sweets also run the gamut -- white sugar is neutral, and brown sugar and honey are base. Vanilla ice cream is acidic, but ice cream with fruit is base. Herbs and vinegars are all base foods.
Because they're made with fruit, most fruit juices are base. The same thing goes for vegetable juices. Tea, coffee, cocoa, mineral water and red and white wines are all base. Sugary sodas are acidic, as are some types of beer. Pale ale is acidic, while stout and draft beers are base.