Macronutrients

• Because it's produced from protein-based animal sources, gelatin is composed almost entirely of protein, containing only trivial amounts of other macronutrients. A standard serving of 1 tablespoon of powdered gelatin yields 6 grams of protein, no carbohydrates and 0.007 grams of fat---half of which is saturated. The protein profile of gelatin reveals high levels of the amino acids glycine, proline, hydroxyproline, glutamic acid and alanine. In addition, gelatin contains most of the essential amino acids, lacking only tryptophan.
  
  

Vitamins and Minerals

• The production process for gelatin---which involves foreign substance removal, boiling and purification---strips the final product of most vitamins and minerals. In its refined form, gelatin contains minute levels of sodium, potassium, riboflavin and folate; one serving of gelatin provides approximately 1 percent of the recommended daily intake for these nutrients. Gelatin also contains a slightly higher concentration of copper, with one serving supplying 8 percent of the recommended daily intake. While other micronutrients---specifically phosphorus, magnesium, iron and calcium---are also present, they appear only in negligible amounts and are unlikely to have much dietary impact.
  
  

Calories

• One tablespoon of powdered gelatin contains 24 calories, nearly all of which come from protein; the minor fat content provides less than 1 calorie per serving. Although gelatin is a calorie-dense food in its dry state, it absorbs between five and 10 times its own weight in water when mixed with liquids during cooking---which increases its volume and drastically reduces its caloric density. In fact, gelatin frequently appears as a substitute for higher-calorie ingredients in products marketed as "lite" and "diet."
  
  

Benefits

• Even though gelatin's nutrient content is sparse, it can boost the biological value of a meal by supplying amino acids that are low or absent in other foods. Its lack of fat and sugar, coupled with a high satiation factor, makes gelatin an excellent product for weight loss diets; it can replace high-fat binding ingredients such as egg yolks and cream. In addition, gelatin may offer specific benefits for sufferers of osteoarthritis. Several of its amino acids---hydroxyproline, arginine and hydrosylysine---facilitate the body's production of collagen, which may protect against the cartilage degeneration found in joint conditions.
  
  

Considerations

• Because pure gelatin is tasteless and odorless, it's typically combined with other ingredients rather than consumed on its own. As a result, the nutritional value of gelatin-containing foods depends largely on the presence of sugar, starches, fats, flavorings and other constituents, which can add calories and alter a food's macronutrient profile. In addition, because it's extracted from animal body parts, strict vegetarians or vegans may eschew products made with gelatin for ethical reasons; plant substitutes include agar-agar, obtained from seaweed, and powdered kuzu root.