- New research indicates that a new diet known as the portfolio diet might help lower LDL cholesterol.
- The portfolio diet is similar to more commonly-known eating plans like the Mediterranean and DASH but places a greater emphasis on plant-based proteins.
- Experts shared the pros and cons of the portfolio diet and ways people can begin to implement it in their everyday lives.
Research suggests a specific diet plan might have heart-healthy benefits, and it’s not the Mediterranean or DASH diets.
A new study published in the peer-reviewed American Heart Association (AHA) journal Circulation on Oct. 25 indicated that adherence to the portfolio diet could lower a person’s risk of stroke and heart disease.
One of the most significant caveats? You might not have heard about it.
The diet was not included in the AHA’s scientific statement on 10 popular heart-healthy diets when it was published in April 2023 (DASH got a perfect score, and the Mediterranean and pescetarian diets were in the top three).
An AHA press release indicates that the reason the portfolio diet was left off is because it’s not common, and the statement evaluated popular plans.
So, what is the portfolio diet?
“The portfolio diet is a specialized dietary pattern aimed at reducing ‘bad’ LDL cholesterol, a key risk factor for heart disease and stroke,” says Dr. Jessica Schachter, DO, an interventional cardiologist at MemorialCare Heart & Vascular Institute at Orange Coast Medical Center in Fountain Valley, Calif. “It comprises specific plant-based foods and components known for their cholesterol-lowering properties.”
Plant-based is a keyword. Whereas DASH and Mediterranean diets don’t discourage lean animal protein, the portfolio diet does.
Components of the portfolio diet
The portfolio diet was created by Dr. David J.A. Jenkins, a Canadian researcher, explains Trista Best, MPH, RD, LD, a registered dietician with Blance One Supplements.
“The portfolio diet is a dietary approach that was developed to help lower cholesterol levels and reduce the risk of heart disease,” Best says. “It is not a specific weight loss diet but rather a way of eating that focuses on incorporating a variety of heart-healthy foods.”
NJ-based dietitian and author of 2-Day Diabetes Diet Erin Palinski-Wade, RD, CDCES, explains there are four components of the portfolio diet:
- Soluble fiber, which is commonly found in foods like oats, barley, and psyllium
- Soy protein, which is in tofu, tempeh, and soy milk
- Plant sterols, which naturally occur in plants like lentils, fruits, and vegetables and might be added to juice and yogurt
- Nuts like almonds, peanuts, and walnuts
Though the portfolio diet isn’t as known as the Mediterranean and DASH, the new study in Circulation is not the first to point to its potential benefits.
For instance, in 2021, research of more than 123,000 postmenopausal women indicated that higher adherence to the portfolio diet lowered instances of cardiovascular and coronary events and heart failure. The authors called for further research in other populations.
Other research from 2021 indicated that the diet lowered low-density lipoprotein (LDL) cholesterol in overweight adults. The optimal range for LDL cholesterol is about 100 mg/dl, according to the CDC, and experts share it’s crucial to be within that range.
“LDL is low-density lipoprotein cholesterol that is also referred to as bad cholesterol,” says Dr. Bradley Serwer, a cardiologist and Chief Medical Officer at VitalSolution. “This form of cholesterol can form plaque within the artery that can limit blood flow or rupture, causing an acute heart attack or stroke.”
And experts share that the foods emphasized in the portfolio diet might have cholesterol-lowering benefits.
“Transitioning to a more plant-based diet rich in high-fiber foods while reducing saturated fat in the diet has been shown to improve blood lipids,” Palinski-Wade says. “In addition, specific foods that are recommended in the diet, such as almonds, have been directly linked with cardiovascular benefits. Adding tree nuts, like almonds, to the diet regularly has been shown to significantly reduce LDL cholesterol levels.”
Palinski-Wade pointed to older research from 2011 that suggested that the nutrients in almonds might help lower LDL cholesterol levels, though authors noted more information is needed to understand why.
Research highlights potential for heart-health benefits of portfolio diets
Unlike the 2021 research on postmenopausal women, the newest study looked at diet data from more than 166,000 women and nearly 44,000 men who did not have cardiovascular disease when they signed up for long-term health studies in the mid-1980s to early 1990s. The participants completed food questionnaires once every four years over 30 years.
“After ranking the participants’ consumption of food in the portfolio diet, those with the highest score had a lower risk of coronary heart disease and stroke,” Schachter says.
The researchers indicated that the people with the highest scores — or those who most closely followed the portfolio diet — had a 14% reduced risk of stroke or coronary heart disease compared to participants with the lowest scores.
Why might the portfolio diet reduce heart risk?
Schachter said its ability to lower LDL cholesterol is critical.
“The benefits of the portfolio diet are multifaceted, as it effectively lowers LDL cholesterol, reducing the risk of heart disease and stroke,” Schachter says. “Maintaining healthy LDL cholesterol levels is vital for cardiovascular health, and the portfolio diet may help achieve this.”
Schachter adds that the portfolio diet provides a heart-healthy, plant-based alternative for people wishing to follow a vegetarian diet with whole, unprocessed foods.
While Schachter says the research is promising, she cautions we still need to learn more about the portfolio diet.
“This research does not provide detailed information on specific meal plans, portion sizes, or daily caloric intake for the portfolio diet,” Schachter says. “Additionally, it might not offer comprehensive comparisons with other diets, such as the DASH diet or Mediterranean diet, in terms of overall health benefits.”
Best agrees that more research is needed.
“Although the portfolio diet has shown promise in short-term studies, there is a need for more long-term research to assess its sustainability and continued benefits over time,” Best says.
Drawbacks of the portfolio diet
The portfolio diet might have its benefits, but experts share it’s not for everyone.
“The main drawback is that many people are unable or unwilling to give up meat and dairy,” Sewer says.
Palinski-Wade says the loose nature of the plan, which doesn’t restrict foods to eat other than discouraging animal protein, offers flexibility — a benefit. But there’s a con to that flexibility, too.
“It may not provide enough guidance to ensure an individual is getting the right balance of macro and micronutrients every day for their own individual needs,” Palinski-Wade says. “For example, individuals who follow a strict vegan version of the diet may need to pay extra attention to ensure they are meeting their nutrient needs, such as vitamin B12, iron, and omega-3 fatty acids.”
It’s always a good idea to consult your healthcare team before starting a new meal plan. Still, Best says specific individuals should exercise particular care before adhering to the portfolio diet, including patients with:
- Allergies or sensitivities, such as to nuts or soy
- Gastrointestinal issues, like irritable bowel syndrome, who may find the high-fiber consumption irritating
- Kidney disease
- A history of eating disorders, who may find the focus on specific foods triggering
- Anyone taking long-term medications for chronic conditions
Best adds that children, as well as pregnant and lactating people, have different nutritional needs. A dietician and doctor can provide insights on whether the portfolio diet is proper for an individual or they can help patients modify it to suit their life stages or conditions.
How to begin following the portfolio diet
Starting a new diet can be challenging, but experts shared the following tips to help people get started.
Transition gradually
Best advises against an all-or-nothing approach at first.
“Start by gradually incorporating the key components of the portfolio diet into your meals,” she says. “This gradual approach allows your taste buds and digestive system to adapt to the changes, making it more sustainable in the long run. It also prevents the diet from feeling overly restrictive.”
Make a plan
Mapping out meals might help increase adherence to the portfolio diet.
“A meal plan can be helpful for grocery shopping, having the right foods on hand, and also to ensure you are meeting all of your dietary needs,” Palinski-Wade says. “You can also work with a registered dietitian to ensure your meal plan is meeting your unique individual needs and health goals.”
Get creative
Perhaps you’ve never eaten much tofu or reached for snacks other than nuts. The portfolio diet can open your mind (and tastebuds) to new foods, which can be fun.
“Experiment with recipes that incorporate the foods emphasized in the portfolio diet,” Best says. “There are numerous creative and delicious ways to include oats, legumes, nuts, and soy into your meals. Exploring new recipes can make the diet more enjoyable and varied.”
Portion control
Though the portfolio diet doesn’t give portion guidance, Best says it’s essential to keep an eye on it.
“Be mindful of portion sizes, especially with calorie-dense foods like nuts,” Best says. “While these foods are healthy, overconsumption can lead to excessive calorie intake, which may not align with your health goals. Portion control ensures that you get the benefits without overindulging.”
Track your cholesterol
Hopefully, the portfolio diet helps individuals with high LDL cholesterol lower theirs, but bloodwork will help ensure that’s happening.
“Monitoring allows you and your healthcare provider to assess the impact of the diet on your health and make any necessary adjustments,” Best says. “This can also provide motivation and accountability.”
Takeaway
The portfolio diet is a lesser-known diet geared toward reducing LDL cholesterol.
Early research and experts indicate that lowering LDL cholesterol can also reduce the risk of cardiovascular disease, so the portfolio diet may be a beneficial tool for individuals with high cholesterol.
That said, it’s not for everyone. The focus on plant-based proteins includes soy, which some people may not tolerate well, and nuts, which some people may be allergic to.
Additionally, not everyone wants to forego animal protein.
Still, people interested in the diet can start small, create meal plans, and use the new eating habits as a reason to get creative in the kitchen.