A diverse diet may not be best for weight loss, according to a science advisory from the American Heart Association (AHA).
Opposing the long-standing belief that a diverse diet is necessary for proper nutrition, the AHA highlighted observational research that instead suggests that a diverse diet may lead to a greater intake of highly processed foods, refined grains, and sugar-sweetened beverages, leading to weight gain and obesity.
In the same vein, aiming for a diverse diet -- rather than a healthy, high-quality diet -- may also lead to less consumption of minimally processed foods, such as vegetables, fruits, and fish, Marcia de Oliveira Otto, PhD, MS, of the Michael & Susan Dell Center for Healthy Living at the University of Texas Health Science Center at Houston, and colleagues wrote in .
The recommendation conflicts with the , which recommends that people "focus on variety" when it comes to their diet and "choose a variety of nutrient-dense foods across and within all food groups in recommended amounts" across a range of vegetables, fruits, grain-based foods like bread and pasta, dairy, and proteins including red meat, poultry, eggs, beans, and nuts.
Instead, the AHA recommended people aim for adequate intake of healthier foods, focusing on a high-quality diet of plants, lean proteins, low-fat dairy, vegetable oils, and nuts to lower disease risk, reflected by the .
"Eating a more diverse diet might be associated with eating a greater variety of both healthy and unhealthy foods" explained de Oliveira Otto in a statement. "Combined, such an eating pattern may lead to increased food consumption and obesity."
"Selecting a range of healthy foods, which fits one's budget or taste, and sticking with them, is potentially better at helping people maintain a healthy weight than choosing a greater range of foods that may include less healthy items such as donuts, chips, fries, and cheeseburgers, even in moderation."
When developing the recommendation statement, the AHA group performed a literature review of observational and interventional studies published between 2000 and 2017 in adults looking at the effects of diet on body weight and obesity.
The AHA advisory also highlighted how the research in this area is largely limited and inconsistent, and thus called for a standardized and reliable measure for diet diversity. The group also called for future research to examine how diet diversity affects long-term cardiovascular and metabolic outcomes and any potential ethnic or racial differences within these clinical outcomes.
"Future research should include stratification by food healthfulness to help identify key food groups that could be targeted to help achieve and maintain healthy weight over time," the statement suggested.
Click for the American Association of Clinical Endocrinologists clinical practice guidelines for healthy eating for the prevention of metabolic diseases.
Disclosures
de Oliveira Otto reported having no relevant disclosures; other statement co-authors did report disclosures.
Primary Source
American Heart Association
de Oliveira Otto M, et al "Dietary diversity: Implications for obesity prevention in adult populations" Circulation 2018; DOI: 10.1161/CIR.0000000000000595.