Saturated Fats – to Limit or Not

As a Registered Dietitian with my own busy counselling practice, I work primarily with patients who are looking to:

1. Lose weight or change their body composition, or
2. Reduce their risk of, or manage, existing cardiovascular disease (CVD).

One of the most common pieces of advice that I give to my patients is to be aware of the types of fats they are consuming, especially for CVD risk and management. I often recommend limiting saturated fat intake while increasing unsaturated fat intake and avoiding trans fats.

However, given the growing popularity of keto and other high-fat diets today, this advice about saturated fats is being questioned by patients in my practice as well as by some academics.

Let’s look at the latest research on the effects of saturated fats on heart health and ask whether our practice guidance needs to be changed.

The Latest Research

The effect of saturated fats on blood lipids was investigated in a systematic review published by the World Health Organization (WHO) in 2016.¹ Researchers evaluated data from over 2,300 adults on the effects of replacing 1% caloric intake from carbohydrates or unsaturated fats with 1% of caloric intake from saturated fat and found that eating saturated fat instead of unsaturated fat or carbohydrates consistently increased lipid and lipoprotein concentrations in the blood.

Yet, a handful of research had also found that there wasn’t enough evidence to conclude that saturated fat increased the risk of heart disease.² It was concluded that more data was needed to understand whether CVD risks are likely to be influenced by the specific nutrients used to replace saturated fat.

Subsequent research has found that when replacing saturated fat with polyunsaturated fats, monounsaturated fats or high-fibre carbohydrates, there are improved outcomes in terms of heart disease in that there were less heart attacks and a lower risk of dying from a cardiovascular event.³ However, the research also showed that replacing saturated fat with highly processed carbohydrates could actually have a negative effect on heart health. In fact, a study published in 2017 found that when sugar and refined carbohydrates replaced saturated fat, the risk of having a heart attack actually increased.³ Ultimately, WHO still recommends limiting saturated fat to a maximum of 10% of the total daily energy intake and replacing saturated fat with unsaturated fat as part of a balanced diet to help reach this goal.^4,5

What you can do for your patients’ heart health

With research-supported heart health benefits from reducing dietary saturated fats, here are a few takeaways for you to consider for your practice:

Small vs Large Changes

• Reducing foods that are high in saturated fats is key to a heart healthy diet, as is adding heart-healthy foods such as plant-based proteins and healthier fats.
• In general, I find that most people do better when making small changes to their diet. If patients dramatically change their eating habits, it is more difficult for them to stick to the healthy changes long term. A small change can be swapping your butter with a soft margarine that is high in unsaturated fats.
• Adding plant-based foods to your diet is a heart healthy idea and is in line with Canada’s Dietary Guidelines.
• Sharing helpful resources like this handout  can help your patients with the first step!

Food Focus vs Nutrient Focus

• We should consider changing our counselling language from a nutrient-focused conversation to more of a food-focused one. If we focus on nutrients in isolation of food choices, it may mean missing a bigger opportunity to talk about how food, diet, health, and lifestyle work together.
• Drawing on the connection between certain plant-based diet patterns as they relate to heart health in different cultures is a great way to help our patients understand the impact of their food choices. For example, we know research supports the benefits of the Mediterranean diet and improved CVD outcomes. We should share this knowledge with our patients.⁶ 

Everyday Nutrition Realities vs. Evolving Nutrition Research

• It seems like one day we learn of one thing coming out of the latest in nutrition research and the next day, we hear of something different. This has got to be frustrating for patients. I’ve found that it has been helpful to have a conversation with my patients around why nutrition research is challenging and complicated ‒ it often needs to factor in multiple diet, health, and lifestyle variables in our lives; the input data is self-reported; we look at predictors for disease and not necessarily endpoints; and food science and dietary influences are constantly evolving and changing. These factors are not always apparent from the news headlines but can be brought to light during conversations with your patients to provide some useful perspective.

In sum, research supports the heart healthy benefits of reducing foods that contain saturated fats, and helping patients add foods to their diets that are rich in plant-based proteins and contain healthier fats.

I hope that the tips provided and this downloadable resource  are helpful in your practice.