The recommended daily fiber intake varies by age, sex, and calorie consumption, but general guidelines for adults are:

• Women under 50: about 25 to 28 grams per day
• Men under 50: about 31 to 34 grams per day
• Women 51 and older: about 22 grams per day
• Men 51 and older: about 28 grams per day

These recommendations come from sources such as the USDA Dietary Guidelines and the FDA Daily Value for fiber on a 2,000-calorie diet

. Another way to estimate fiber needs is based on calorie intake: about 14 grams of fiber per 1,000 calories consumed daily

. For example, a 2,000-calorie diet would suggest about 28 grams of fiber. Most experts and health organizations recommend a total fiber intake of 25 to 30 grams per day from food sources, not supplements

. This intake supports digestive health, cardiovascular health, and may reduce risks of chronic diseases. Children require less fiber, with amounts increasing as they grow older—ranging from about 14 grams for toddlers to 25-31 grams for teenagers depending on age and sex

. Since average fiber intake in many populations is below recommendations (often around 15-20 grams per day), increasing intake through fruits, vegetables, whole grains, legumes, nuts, and seeds is advised

. In summary, aiming for about 25 to 30 grams of fiber daily from a variety of whole food sources is optimal for most adults, with adjustments based on age, sex, and calorie needs.