How do you know the difference between a good fat and a bad fat?
The same question applies to carbohydrates and proteins. These foods, known as macronutrients, are the basic categories of nutrients that humans need. They provide the body with energy, and they enable the body to carry out many normal biological functions. A healthy diet consists of a mix of foods from each of these three macronutrient categories, although not in equal amounts.
The latest science tells us that instead of focusing on individual nutrients, it’s best to think about your overall dietary pattern. Try for a mix of whole foods from nature, not factory-made foods, with a variety of sources of fats, carbs, and proteins.
There is no one healthy diet, but many, from around the world. One example of a healthy mix of fats, carbohydrates, and proteins is the Mediterranean diet; another is known as the DASH (Dietary Approaches to Stop Hypertension) diet (see “Eating plans for good health”). It and variations known as DASH-style diets are high in fruits and vegetables and healthy plant oils.
A panel of U.S. and Canadian scientists backed by the National Academy of Sciences’ Institute of Medicine has set dietary reference intakes (DRIs) for macronutrients based on research on diet and health (see “How much of each?”). The DRIs set forth the range of macronutrients in a diet balanced to maintain a healthy weight and to prevent serious conditions such as heart disease, cancer, hypertension, and diabetes. The DRIs also provide guidelines for fiber (a form of indigestible carbohydrate that serves several functions in the body) and vitamins and minerals.
How much of each? Following are the dietary reference intakes (DRIs) for fats, carbohydrates, and proteins — the amounts needed daily to meet nutritional needs for adults while minimizing risk for disease. But keep in mind that more important than strictly adhering to these percentages is making sure to choose healthy sources for fats, carbohydrates, and proteins, as described in this report.
- Fats: 20% to 35% of daily calories (reduce saturated and trans fats as much as possible while consuming a nutritionally adequate diet).
- Protein: 10% to 35% of daily calories.
- Carbohydrates: 45% to 65% of daily calories (reduce consumption of added sugar).
- Fiber (indigestible carbohydrate): 14 grams per every 1,000 calories.
- That’s about 21 to 38 grams a day, based on age and sex, as follows:
- men ages 50 and younger: 38 grams/day
- women ages 50 and younger: 25 grams/day
- men over age 50: 30 grams/day
- women over age 50: 21 grams/day.
Dietary Reference Intakes: The Essential Guide to Nutrient Requirements, Institute of Medicine (National Academy of Sciences).