According to a statement from the American Heart Association, several popular eating patterns rank high for heart health; some however contradict the AHA’s dietary guidelines and didn’t rank as heart-healthy.
The number of various, popular eating patterns has proliferated in the past few years, as well as the amount of misinformation circulating on social media which can add confusion to heart-healthy eating.
Cardiometabolic health represents a set of factors such as body weight, blood pressure, blood glucose, cholesterol and other lipids that impact metabolism and the risk of vascular and heart disease.
Though abnormal levels of 1 factor could increase heart disease risk, the risk increases even more as well as risk for more severe disease with abnormal levels in more than 1 factor.
The statement ranks how well popular eating patterns align with the AHA’s Dietary Guidelines. The guidelines include 10 key features of an eating pattern for improving cardiometabolic health, which focuses on the limitation of unhealthy fats and reducing excess carbohydrate consumption.
This balance optimizes both general metabolic and cardiovascular health and limits other health condition risks that could be a consequence of excessive carbohydrate consumption, especially sugar-sweetened drinks and processed carbohydrates, which are both associated with increased cardiovascular disease risk.
The statement analyzes how popular dietary patterns comply with those characteristics, and the guidelines are tailored to being flexible to individual budgets in addition to cultural and personal preferences.
The defining characteristics of a few dietary patterns intended to be adhered to long-term were reviewed. Dietary patterns were arranged by similarity in key features, resulting in 10 groups:
- DASH-style diet – represents a dietary pattern that emphasizes fruits, veggies, legumes, whole grains, low-fat dairy, seeds and nuts, and includes non-tropical oils, lean poultry and meats, and fish. The Baltic and Nordic diets are other kinds of this dietary pattern.
- Mediterranean-style diet – also called the Mediterranean diet, this pattern restricts dairy; emphasizes fruit, veggies, legumes, whole grains, seeds and nuts, extra virgin olive oil, and fatty fish; and includes moderate red wine consumption.
- Vegetarian/Pescatarian style diet – a plant-based dietary pattern that includes fish.
- Vegetarian/Ovo/Lacto style diet – plant-based dietary patterns that include dairy products (lacto-vegetarian), eggs (ovo-vegetarian), or both (lacto-ovo vegetarian).
- Vegetarian/Vegan style diet – a plant-based dietary pattern that excludes all animal products.
- Low-fat diet – a diet that restricts the consumption of fat to less than 30% of total calorie intake, including the Therapeutic Lifestyle Change and the Volumetrics dietary plans.
- Very low-fat diet – a diet that restricts the consumption of fat to less than 10% of total calorie intake, including the Physicians Committee for Responsible Medicine, McDougal, Pritikin, Esselstyn, and Ornish diets. Some could also be considered vegan.
- Low-carbohydrate diet – a diet that restricts carbohydrate consumption to between 30 and 40% of total calorie intake, and includes Zone, South Beach, and low GI diets.
- The Paleolithic diet – also called the Paleo diet, excludes dairy legumes, whole and refined grains, and oils.
- Very low-carbohydrate/ketogenic diet – restricts the consumption of carbohydrates to less than 10% of daily calorie intake and includes the Well-Formulated Ketogenic, Atkins, and Ketogenic diets.
Each diet was assessed against 9 of the 10 characteristics of the AHA’s guidelines for a heart-healthy dietary pattern. The only factor not made use of in scoring was “consuming to reach an appropriate energy balance for maintaining a healthy weight,” as this is affected by other factors besides dietary choices, which include physical activity levels and is applicable to all the diet groups equally.
Defining characteristics of the diets were allocated points according to how well each characteristic aligned with the AHA’s guidelines: 1 point for fully reaching the guidelines, 0.75 points for mostly reaching the guidelines, and 0.5 points for partially reaching the guidelines.
If a factor in the diet didn’t meet the guidelines at all, zero points were allocated for that factor. The generated scores were totaled and revised to provide a rating between 0 and 100, with 100 being the closest adherence to AHA’s dietary guidelines.
The eating patterns reviewed varied greatly in their alignment with AHA guidelines, producing scores between 31 and 100. The scores were grouped into 4 levels, and diet factors that helped adhere to the guidelines and also potential adherence challenges were taken into account.
The only factor of the guidelines that was part of every dietary pattern was “minimize the consumption of beverages and foods with added sugars”. Opportunities to improve the healthy aspects of each dietary pattern were also identified.
Level 1: Highest-rated dietary plans scoring higher than 85
The 4 highest-rated dietary patterns are adaptable and provide a wide range of healthy food choices. The DASH-style dietary pattern earned a perfect score by reaching all of the AHA’s guidelines. These dietary patterns are low in processed foods, added sugar, salt, tropical oils, and alcohol, and abundant in fruits, non-starchy veggies, legumes, and whole grains.
Protein is mainly from plant sources which include nuts, beans, or legumes along with seafood or fish, lean meats and poultry, and fat-free or low-fat dairy products.
The Mediterranean-style diet also has a high rating. It has a slightly lower score compared to DASH as it doesn’t deal with added salt and includes moderate consumption of alcohol instead of restricting or avoiding alcohol. Also, the majority of the characteristics of a vegetarian dietary pattern align with the AHA’s dietary guidelines. Vegetarian and pescatarian dietary plans that include dairy, eggs, or both were also in the top level.
The top-level dietary patterns align best with the AHA’s guidelines if applied as intended and could be adapted to respect budgets, food preferences, and cultural practices to enable individuals to always eat in such a manner in the long term.
Level 2: Low-fat and vegan diets scoring between 75 and 85
Low-fat and vegan diets also emphasize the consumption of fruits, veggies, whole grains, nuts, and legumes, while restricting alcohol and beverages and foods with added sugar. Restrictions in the vegan dietary pattern could however make it more challenging to adhere to when dining out or in the long term.
Adhering to a vegan dietary pattern could increase the risk of deficiency in vitamin B-12, which could lead to red blood cell abnormalities resulting in anemia; supplementation could therefore be recommended.
All fats are often treated equally in low-fat diets, while the AHA’s guidelines suggest substituting saturated fat with healthier fats which include poly and monounsaturated fats. Individuals who adhere to a low-fat diet could over-eat less healthy carbohydrate sources, which include refined grains and added sugars. T
hese factors could however be overcome with proper education and counseling for individuals interested in these dietary patterns.
Level 3: Low-carb and very low-fat diets scoring between 55 and 74
These dietary patterns align low to moderately with the AHA’s guidelines. Motivation for some individuals to adhere to a very low-fat diet could be that some research has found they potentially reduce the progress of artery fat build-up.
A healthy low-carbohydrate dietary pattern has been found to influence cholesterol, blood sugar, blood pressure, and weight loss equally in comparison to a healthy low-fat diet. Both dietary patterns however limit food groups that the AHA’s guidelines emphasize.
Points were lost for limiting healthy plant oils and nuts in very low-fat diets. This dietary pattern could also lead to deficiencies of protein, essential fatty acids, and vitamin B-12, resulting in muscle weakness and anemia.
Low-carb diets limit fruits because of the sugar content, legumes, and grains. In limiting carbohydrates, individuals are likely to reduce fiber consumption while increasing saturated fat consumption from meats and animal-sourced foods, both of which contradict the AHA’s guidelines.
The statement indicates that loosening limitations on food groups which include whole grains, fruits, seeds, and legumes could help individuals stick to a reduced carbohydrate dietary pattern while promoting long-term heart health.
Level 4: Very low-carb/Ketogenic and Paleolithic diets scored less than 55
These 2 dietary patterns, often made use of for losing weight, don’t align well with the AHA’s dietary guidelines. The very low-carb dietary pattern’s strengths are the emphasis on eating non-starchy veggies, nuts, and fish, together with reducing added sugar and alcohol consumption. Blood sugar and body weight improvements have been found with these diets In studies as long as 6 months.
However, the majority of improvements after a year were no different compared to those of a less restrictive diet. Limitations on legumes, whole grains, and fruits could lead to reduced fiber consumption. These diets are also high in fat without restricting saturated fat. The consumption of low fiber levels and high saturated fat levels are both associated with the risk of cardiovascular disease.
There isn’t any way to adhere to the Level 4 diets as intended and still align with the AHA’s Dietary Guidelines. They are highly limited and difficult for the majority of individuals to adhere to long term. Although they probably have short-term benefits and significant weight loss, they aren’t sustainable. Diets that are effective at helping a person maintain weight loss goals practically have to be sustainable.