Move over, Mediterranean diet. The nation’s preeminent organization dedicated to improving heart health has endorsed the lesser-known ‘portfolio diet’.
Much like diversifying a stock portfolio with different promising investments, the ‘portfolio diet’ involves incorporating various healthy dietary patterns together.
It was invented by researchers from Harvard University T.H. Chan School of Public Health and is made up of a range of cholesterol-lowering foods.
It’s not as well-known as other popular diets such as the Mediterranean diet or the DASH diet, but it shares many similarities.
It’s not as well-known as other popular diets such as the Mediterranean diet or the DASH diet, but the ‘portfolio diet’ shares many similarities
For instance, followers are encouraged to swap in plant-based proteins instead of red meat and eat lots of complex fibrous foods like oatmeal and healthy fats like nuts.
But the portfolio diet is more plant-forward and discourages animal proteins more than other dietary patterns.
‘We want people to look at the combinations of foods — in real diets for real people in the real world — that will carry off, as in the financial world, a range of benefits weighted against reducing a range of risks,” Dr. David J.A. Jenkins, creator of the Portfolio diet, told WedbMD.
The Portfolio diet is not designed for weight loss. Rather, its main goal is heart health.
People who followed the diet for 30 years had a 14 percent lower risk of coronary heart disease and strokes compared to people who followed a standard diet.
The Harvard researchers published their findings in the American Heart Association’s journal Circulation, signaling that the preeminent heart health organization endorses the diet plan as a highly effective way to prevent cardiovascular disorders.
Dr. Andrea Glenn, a nutrition expert at Harvard and co-author of the study, said: ‘Through this research, we found that the portfolio diet score was consistently associated with a lower risk of both heart disease and stroke, highlighting an opportunity for people to lower their heart disease risk through consuming more of these foods recommended in the diet.’
Previous research has shown that following the portfolio diet rich in cholesterol-lowering foods is about as effective as medication. But little has been known about the diet’s benefits long-term until now.
The team conducted their research on more than 210,000 healthcare professionals enrolled in three different nationally representative studies into risk factors for severe diseases that began recruiting in the 1980s.
They issued food frequency questionnaires asking study subjects to look at a limited checklist of foods and beverages with a frequency response section for subjects to report how often they consumed each item.
Participants filled out the questionnaire at the start of the study and every four years after that for 30 years.
The food frequency questionnaire was used to develop a Portfolio Diet Score (PDS), which assigns points for consuming higher amounts of approved foods and subtracts points for consuming foods that negatively impact cholesterol levels, such as saturated fats or trans fats.
The goal is to lower LDL cholesterol specifically, as this type of ‘bad’ cholesterol is strongly linked to heart disease risk.
The researchers said: ‘This dietary pattern also aligns with the American Heart Association guidelines promoting the consumption of whole grains, fruits and vegetables, healthy plant-based proteins, minimally processed foods, and healthy unsaturated plant oils.’
During the 30-year follow-up, researchers recorded 16,917 cases of cardiovascular disease, including 10,666 cases of coronary heart disease and 6,473 strokes.
People who scored highest on the PDS had a 14 percent lower risk of developing heart disease and stroke.
And for each 25-percentile increase in the PDS, the risk of total cardiovascular disease, including coronary heart disease and stroke, declined by eight percent.
Using blood plasma samples to measure the effects, researchers found that the diet was linked with lower levels of inflammation in the body, which promotes the buildup of harmful plaques made up of LDL cholesterol in the arteries, causing them to narrow and impede normal blood flow.
This drastically raises one’s risk of experiencing a heart attack or stroke.
The study did not focus on weight loss, which is often people’s goal when they embark on another diet such as Keto, Mediterranean, and DASH.
Dr Kristina Petersen, a nutrition expert at Penn State University who co-authored last spring’s AHA statement scoring 10 popular diets for their heart-health benefits, said: ‘We’re always looking at ways to reduce the risk of heart disease, and one effective way to do that is to lower blood cholesterol levels, particularly LDL cholesterol.’
The only reason the portfolio diet was not included in that list, Dr Petersen said, was because ‘it’s not particularly common.’
She added: ‘It’s not an all-or-nothing approach. You can take your own diet and make a few small changes and see cardiovascular benefits.
‘You also do not have to follow it as a strict vegan or vegetarian diet to see benefits, but the more of the foods (from the portfolio diet) that you eat, the greater your heart disease risk protection, as we saw in the current study. We need to get the word out.’