Diet, low fat

Related Terms

Diet, low fat, low-fat.

Background

Eating a diet that is low in fat and high in nutritional value has long been advocated by many major US health organizations as a key component to staving off heart disease, type II diabetes, stroke, and most other adult-onset chronic diseases.
A recent, long-term study, however, called into question the truth of these claims. The Harvard School of Public Health takes serious issue with low fat diets because they restrict consumption of all fats, rather than only the most harmful ones.
Advocates of low fat diets also encourage consumers to purchase reduced and no-fat versions of foods, even if those foods contain artificial sugars such as aspartame, or contain higher levels of calories.

Theory / Evidence

According to the United States Department of Agriculture (USDA), caloric intake should be balanced with an individual's level of physical activity. A majority of Americans spend their time doing sedentary tasks, such as typing or watching TV. Fatty foods contain more calories; more physical activity is required to burn these calories.
Based on one study, patients with type I diabetes who adopted a low fat diet improved their sensitivity to insulin.
A long-term, in-depth study found that a low fat diet does not lower the risk for heart attacks, colon cancer, strokes, or breast cancer. The study suggested instead a more comprehensively healthy life-style, even if that life-style does include some healthy fats.
In sum, the overall evidence is mixed as to whether this diet may be beneficial for all patients. More evidence is needed before any firm recommendations can be made.

Author information

This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

Bibliography

American Medical Association. Roadmaps for Clinical Practice series: Assessment and Management of Adult Obesity. 18 May 2006.
Harvard School of Public Health: Fats & Cholesterol. 17 May 2006.
Nutrition and Your Health: Dietary Guidelines for Americans from the USDA. 16 May 2006.
Prentice RL, Caan B, Chlebowski RT, et al. Low-fat dietary pattern and risk of invasive breast cancer: the Women's Health Initiative Randomized Controlled Dietary Modification Trial. JAMA. 2006 Feb 8;295(6):629-42.
Rosenfalck AM, Almdal T, Viggers L, et al. A low-fat diet improves peripheral insulin sensitivity in patients with Type 1 diabetes. Diabet Med. 2006 Apr;23(4):384-92.

Technique

Even when people eat fewer high fat foods, they can still eat in an unhealthy manner by consuming foods that are high in starch, sugars, and protein, but devoid of more complete nutritional value. The USDA recommends that patients choosing a low fat diet also eat plenty of foods with documented nutritional value, such as vegetables, low fat dairy products, and whole-grains.
The American Medical Association recommends changing eating patterns, such as adopting substitutions, rather than meticulously counting calories or grams of fat. The exact number of calories is not as important as portion control and making everyday healthy selections of lower fat foods. They also suggest a gradual change in diet in order to prevent feelings of deprivation and withdrawal.
The medical profession's opinion of low fat diets is currently in flux. Patients are encouraged to discuss any diet with their doctor.