Lowering cholesterol: the portfolio diet

Raised cholesterol is a common problem, which I see many times in the clinic. Genetic predisposition, a typical Western diet and existing metabolic imbalances could be contributing factors. Many people believe it is dietary cholesterol in foods that raise blood cholesterol, while it is actually saturated fats in foods that raise it! A very dietary intervention that according to studies can lower blood cholesterol levels by up to 30% is the portfolio diet. Let me explain what it is. 

Understanding the portfolio diet:

The portfolio diet, developed by Dr. David Jenkins and his colleagues at the University of Toronto, amalgamates a synergistic array of cholesterol-lowering foods. Unlike conventional low-fat diets, the portfolio diet emphasises the incorporation of specific plant-based foods, each renowned for its cholesterol-lowering prowess. These include viscous fibres (e.g., oats, barley, psyllium), nuts, plant sterols, and soy protein.

The science behind cholesterol reduction:

The efficacy of the portfolio diet stems from the collective impact of its constituent foods on various lipid parameters. Viscous fibres, for instance, form a gel-like matrix in the gut, impeding cholesterol absorption and facilitating its excretion. Nuts, abundant in heart-healthy fats and phytochemicals, exert potent cholesterol-lowering effects while conferring cardiovascular protection.

Plant sterols, structurally akin to cholesterol, competitively inhibit its absorption, thereby reducing circulating levels. Furthermore, soy protein, rich in isoflavones, not only can displace animal protein but can also modulate lipid metabolism, fostering a favourable blood lipid profile.

Implementing the portfolio diet:

Embarking on the portfolio diet journey necessitates a comprehensive dietary overhaul, characterised by the strategic inclusion of cholesterol-lowering foods. Individuals aspiring to adopt this dietary regimen should prioritise whole grains, legumes (beans, chickpeas, lentils edamame beans), fruits, vegetables, tree nuts, and soy-based products (tofu, tempeh, miso, natto, edamame beans). Regular consumption of specific foods, such as oats, barley, almonds, and soy milk, can serve as cornerstones of this dietary approach. Moreover, attention to portion sizes and overall caloric intake remains imperative to optimise cholesterol-lowering outcomes.

Navigating the downfalls:

While the portfolio diet boasts impressive accolades in the realm of cardiovascular health, it is not devoid of potential pitfalls. One notable caveat pertains to the feasibility and sustainability of long-term adherence. Given the restrictive nature of this dietary pattern, some individuals may encounter challenges in maintaining compliance, particularly in social settings or amidst culinary temptations. Additionally, concerns regarding nutrient adequacy may arise, necessitating vigilant monitoring of key nutrients, such as vitamin B12, calcium, and omega-3 fatty acids.

Furthermore, individuals with nut allergies or soy intolerance must exercise caution and seek personalised dietary guidance to avert adverse reactions. An alternative dietary pattern that can effectively help manage raised cholesterol levels is the Mediterranean diet, which features plenty of vegetables, healthy fats from olive oil, oily fish and nuts, whole grains, legumes and lean proteins.

In conclusion, the portfolio diet is a powerful tool to manage elevated cholesterol levels, but it can be hard to follow due to its restrictive nature. Avoid a DIY approach to truly benefit from this diet’s benefits and refer to a healthcare professional to be sure it is balanced and avoid nutritional deficiencies.