Dietary trends in the United States. Relevance to cancer prevention.

BACKGROUND

Diet may be an important factor in the cause and prevention of cancer. Thus, in part to reduce cancer risk, the United States has set two dietary goals for the Year 2000: to reduce fat intake by 18% so that fat constitutes no more than 30% of caloric intake (baseline level 35%), and to double the consumption of carbohydrate and fiber-containing foods by increasing fruit and vegetable consumption to five servings per day and grains to six servings per day (baseline levels 2.5 and 3.0). How far the US population has progressed toward these goals is uncertain.

METHODS

Dietary trends in the United States during the past 20 years were examined by compiling food supply data and dietary intake estimates from US adults from various national surveys and from individual studies.

RESULTS

Dietary fat intake, considered in absolute terms and as the proportion of calories derived from fat, has been declining slightly during the past 20 years but probably remains near 35% of kilocalories derived from fat. Fruit and vegetable intake appears to be increasing, yet probably averages no more than 3.4 servings per day among US adults. These dietary trends may not be occurring equally in all socioeconomic levels of our society.

CONCLUSIONS

There is evidence of modest improvement in the American diet during the past 20 years, with decreasing fat and increasing fruits and vegetables in the diet, but changes must occur at a faster pace if the Year 2000 dietary goals are to be met. More cost-efficient and more timely methods of dietary surveillance of target populations must be developed to support the development and evaluation of more effective dietary interventions.