The food pyramid is the long-accepted standard for nutrition advice in the US, but there are now many scientific studies that challenge the validity of this traditional set of suggestions for the optimal daily intake of proteins, fats and carbohydrates. While the food pyramid may have served the general public well in the past, its flaws become more apparent the closer one looks at it.
How the Pyramid Was Built
The USDA’s first nutrition guidelines were published in 1894 in the form of a farmers’ bulletin. The association with the agricultural industry would continue until the present day, introducing the risk of moral hazard, meaning that the Department’s recommendations were colored by the interests of industry.
The ‘Basic 7’ food groups were introduced in 1943:
- Green and yellow vegetables (some raw; some cooked, frozen or canned)
- Oranges, tomatoes, grapefruit (or raw cabbage or salad greens)
- Potatoes and other vegetables and fruits (raw, dried, cooked, frozen or canned)
- Milk and milk products, including cheese
- Meat, poultry, fish, or eggs (or dried beans, peas, nuts; or peanut butter)
- Bread, flour, and cereals (natural whole grain; alternatively, enriched or restored grain)
- Butter and fortified margarine (with added Vitamin A)
From 1956 until 1992, the United States Department of Agriculture recommended the ‘Basic Four’ food groups:
- fruit and vegetables
- bread and cereals.
The food guide pyramid from 1992 sought to quantify the recommended servings of each food group.
The newest guidelines, published in 2015, have come under criticism for, again, being too influenced by the agriculture industry. Specifically, omission of high-quality evidence was alleged. That same year, the committee included ‘environmental sustainability’ in its recommendations, finding that a plant-based diet was better for the environment than one rooted in dairy and meat – making it unclear whether the USDA was primarily concerned with recommending ways to eat a balanced diet or save the environment.
Not as Rock Solid as One Might Believe
A recent study published by the American Medical Association examines the impact of a diet based on the food pyramid versus diets with different macronutrient ratios. The results show that while people who followed the food pyramid as instructed did lose some weight while improving their lipid profile (i.e. cholesterol and triglycerides), those same individuals experienced no decrease in blood pressure or improvements to other markers of cardiovascular risk. Furthermore, those who followed a different macronutrient ratio outside the suggested guidelines achieved better overall health outcomes than those who stuck strictly to the food pyramid’s instructions. This suggests that relying solely on the food pyramid for nutritional advice may not be ideal for optimal health.
Another issue with the food pyramid is that it fails to account for individual nutritional needs. A person’s age, activity level, and body composition all play a role in what types and amounts of nutrients they require each day, yet the food pyramid does not factor these into consideration, as it recommends nutrient intake for all individuals, regardless of individual differences. For example, an endurance athlete would likely need more carbohydrates than an older adult who is sedentary; yet both would go by the same instructions if following the food pyramid.
Finally, there are several components of optimal nutrition missing from the USDA’s recommendations, including Omega-3 fatty acids and dietary fiber, not to mention certain vitamins and minerals. All these are important components of a plan aimed at general good health, linked to disease prevention and longevity, yet they are not given enough attention in the current guidelines.
In conclusion, while attempting to follow a diet based upon traditional dietary recommendations, such as those provided by the current version of the USDA’s nutritional guidelines, can provide some benefit in terms of weight loss, these benefits do not necessarily translate into improved overall health outcomes as compared with diets which include additional macronutrients or suggest different intakes.