Hay Diet

This diet was developed by the American physician Howard Hay. He suffered from kidney disease and claimed to have healed himself with the diet he developed. In the Hay diet, foods consisting mainly of protein should not be eaten together with carbohydrate-containing foods in the same meal. According to Hay, humans cannot digest both nutrients at the same time. The carbohydrates should reach the small intestine undigested, where fermentation and acid breakdown occur. Hay assumed that all diseases and obesity were caused by too much acid in the tissue. Here the separation of carbohydrates and protein protects the body is to be protected from over-acidification and illness.

Hay divided foods into acidic and base groups, whereby animal foods mainly belong to the acids, and plants to the bases.

Acid and base foods

Strong acid-forming Slight acid-forming Slight acid-forming Strong base forming
Meat, sausage, fish Quark Dried fruit Vegetables, leafy salads
Eggs, cheese Cream Raw milk Fresh fruit
Cakes and other sweet baked goods, white flour products Wholemeal products Mushrooms Potatoes
Alcohol, coffee      

The Principle of Hay Diet

  • Carbohydrates should not be consumed together with protein products and citrus fruit.
  • Vegetables, fruit and salads form the basis of the diet.
  • Protein, carbohydrates and fats should be consumed in limited quantities.
  • Avoid foods that are heavily processed and contain artificial substances.
  • Wait a period of four to six hours between full meals. Avoid snacks between meals.
  • "Neutral" foods may be eaten together with protein as well as carbohydrates.
  • Half of the meal should consist of fresh fruit and vegetables.

Food selection

Protein-rich Carbohydrate-rich Neutral
Meat Cereals Animal fats
Poultry Bread, cake Oils
Fish Pasta Cheese > 50 % fat
Seafood Potatoes Nuts
Eggs Sugar Fruits
Soy products Rice Vegetables
Dairy products < 50 i.Tr. Bananas  

The Hay diet avoids legumes because they contain relatively large amounts of protein and carbohydrates and therefore do not fit into the diet concept.