Direct answers to common food questions and careful checks of popular nutrition and cooking claims.
A kilocalorie always represents the same amount of energy, but that does not mean the body processes every food that supplies it identically. Protein, fat, carbohydrate, fiber and food structure differ in digestion cost, absorption and fullness. This article focuses on that physiology; the nutritional quality of two equally caloric foods is a separate question.
Every ultra-processed food is processed, but not every processed food is ultra-processed. Freezing vegetables, pasteurizing milk, canning beans or fermenting yogurt all process food without automatically making it ultra-processed. In NOVA, ultra-processed foods are industrial formulations that go well beyond preserving or preparing the original food.
An ultra-processed food is not defined simply by coming from a factory, being wrapped in plastic or having a long ingredient list. In NOVA, it is typically an industrial formulation built largely from refined ingredients or substances derived from foods, often combined with flavors, emulsifiers, colors, sweeteners or other additives that shape taste, texture and appearance.
Processing a food does not automatically make it unhealthy. Freezing vegetables, pasteurizing milk, fermenting yogurt, cooking beans or canning fish can improve safety, shelf life and convenience while preserving much of the food's nutritional value. What matters is the specific process, what gets added or removed, and the final food.
You do not need to rinse every kind of rice. With basmati and other long-grain varieties, rinsing can remove loose surface starch and help the grains stay more separate; with risotto and some other dishes, that may not be the goal. Ordinary rinsing also has little effect on inorganic arsenic and does not sterilize rice, so texture, arsenic, and food safety are best treated as three separate questions.
When the surface of a recently cut avocado turns brown, it is usually enzymatic oxidation rather than spoilage. The appearance changes much faster than the overall nutrition. You can scrape away a thin layer if you dislike the taste or texture. Mold, a rotten or strongly fermented smell, pronounced slime or deep widespread deterioration point to a different problem.
The white material that appears on salmon during cooking is protein from the fish pushed out with water and then coagulated by heat. It is commonly called albumin. It is safe to eat and does not by itself mean the fish is spoiled or contains parasites. More tends to appear when cooking is especially hot or prolonged.
The answer depends mainly on texture. On a solid block of hard cheese, a small patch of accidental mold can be removed by cutting at least 1 inch (2.5 cm) around and below it without dragging the knife through the mold. Soft or fresh cheese, plus shredded, sliced or crumbled cheese, should be discarded because growth can extend beyond what you can see. Intentional mold in blue cheese or Brie is a different case.
Yes. In the United States, commercially sold shell eggs should be refrigerated promptly at 40°F (4°C) or below and kept cold until use. U.S. eggs are commercially washed and normally sold under refrigeration, so storing them on the counter after purchase breaks that cold chain. Keep the carton on an interior refrigerator shelf and take out only the eggs you are about to use.
You do not have to combine grains and beans in the same meal for plant protein to ‘work.’ What matters is enough total protein and a variety of sources across the day. Rice and beans are a useful combination, not a biochemical requirement at every plate.
A complete protein provides all nine essential amino acids in proportions high enough relative to a reference pattern. A so-called incomplete protein usually contains those amino acids too; one is simply present in a lower proportion and becomes the limiting amino acid.
Nuts are high in calories because they pack a lot of fat into very little water: a 1-ounce serving usually provides about 155–200 calories. That does not make them nutritionally poor; most of their fat is unsaturated, and the same handful also provides protein, fiber, vitamins and minerals.