We’re all aware of the risks of having high cholesterol, specifically LDL (low density lipoprotein) cholesterol, as it increases your risk of cardiovascular disease, including heart disease and strokes. The high levels of LDL can cause fatty deposits, known as plaques, to build up in your arteries. These plaques can reduce blood flow so your heart and brain may not get the oxygen blood flow it requires, increasing risk of a heart attack or stroke.
Whilst having high cholesterol can be inherited, it’s often preventable by eating a healthy diet and exercising. There are many types of medication which can be taken to reduce high cholesterol but prevention is better than cure. This week, a systemic review and meta-analysis was published which examined the Portfolio diet, a type of diet believed to reduce LDL-cholesterol levels.
A study in the Journal of the American Medical Association (JAMA) in 2011[i] found that a vegetarian diet containing portfolio of cholesterol lowering foods was more effective at lower LDL-cholesterol levels than a low saturated fat vegetarian diet, and in preventing heart disease. These portfolio foods included
Plant protein from soy based foods or pulses
Foods with soluble fibre such as oats, barley, apples, aubergines, oranges etc
Margarine enhanced with plant sterols, or cholesterol like compounds found in fruits, vegetables, nuts and cereals
As a result, several countries have recognised the importance of this work in their guidelines for treating high cholesterol levels through lifestyle interventions. The European Study of Diabetes commissioned a report on all the studies and evidence available summarising the benefits of the Portfolio diet on cardiovascular health and the first review[ii] was published last month.
Whilst plant based diets have been found to improve heart health in previous observational and clinical trials, the Portfolio diet has been shown to have more significant results in reducing LDL cholesterol levels which leads to clinical implications for improving heart health.
This Portfolio diet specifies that participants have a daily intake of 42g of nuts, 20g soluble fibre, 50g plant proteins and 2g of plant sterols. This review found that adhering to the diet lowered LDL cholesterol by 17%, as well as triglycerides (the most common type of fat in the body), blood pressure and C-reactive protein (a common marker of inflammation). It also showed that it decreased the risk of coronary heart disease by 13% over a decade.
So how does this translate into what we should eat to reduce LDL-cholesterol levels? Whether you are vegetarian or not, these guidelines advise to increase the amount of plant based protein eaten ie in the form of pulses, beans, legumes and soya beans, eat more oats, barley and vegetables and fruits, and 42g of nuts a day. Many vegetables and nuts include plant sterols including sesame seeds, olive oil, almonds and herbs such as sage, thyme, oregano and paprika. Not surprisingly, many of these foods are part of what is known as the Mediterranean diet which is known to be a heart healthy diet – our all time favourite disease protecting diet!
[i] Effect of a dietary portfolio of cholesterol-lowering foods given at 2 levels of intensity of dietary advice on serum lipids in hyperlipidemia: a randomized controlled trial. – Jenkins et al, JAMA. 2011 Aug 24;306(8):831-9
Chiavaroli et al
Prog Cardiovasc Dis. 2018 May 25