The Effects on Health and Death of Dietary Fat and Carbohydrate IntakeMar 01, 2018
Mahshid Dehghan et al. Associations of fats and carbohydrate intake with cardiovascular disease and mortality in 18 countries from five continents (PURE): a prospective cohort study. The Lancet August 2017 (published online).
The PURE Study
Some of you may have heard about this study in the media when it was published this past fall. Over 135,000 individuals of both genders and all ages in 18 countries in 5 continents were studied. Participants included rich and poor, meat-eaters and vegetarians. Diet was measured using validated diet questionnaires (not 100% accurate but the best possible strategy when including over 135,000 people). Intakes of carbohydrate, total fat, saturated fat, monounsaturated fat and polyunsaturated fat as a percent of total calories were calculated.
- Blood lipid levels (LDL, HDL and total cholesterol, apolipoprotein A and B),
- Number of cases of cardiovascular disease (heart attack and stroke)
- A number of deaths.
Needless to say, the statistics needed to sort out such a huge amount of data are very complicated and beyond my ability to judge the suitability. I am trusting the study was done using a fair methodology. The protocol controlled for numerous variables that affect diet such as poverty, exercise levels, gender, age and more.
The findings: ↑ - increased
↔ - correlates with
↓ - decreased
- ↑ carbohydrate intake ↔ ↑ risk of death. The higher the intake – the higher the death rates. Recommended carbohydrate intake is less than 60% of calories.
- ↑ total fat intake and ↑ intake of each individual type of fat ↔ ↓ total mortality. Recommended fat intake is about 35% of total calories.
- ↑ protein intake ↔ ↓ mortality from both cardiovascular and non-cardiovascular causes. The subjects got between 10 -18% of their calories from protein (South Asians which includes India which is vegetarian eats the least protein. South Americans and Southeast Asians eat the most protein).
- Total fat and types of fat were not associated with cardiovascular disease, myocardial infarction, or cardiovascular disease mortality.
- ↑ saturated fat ↔ ↓ stroke.
Could 70 years of dietary advice about the benefits of low fat be wrong?
The authors find fault with the advice that has been given for decades that fat and saturated fat in particular increase rates of heart disease and death. See the current recommendations of HeartandStroke.ca to read this incorrect advice.
The authors conclude “Our findings do not support the current recommendation to limit total fat intake to less than 30% of energy and saturated fat intake to less than 10% of energy. Individuals with high carbohydrate intake might benefit from a reduction in carbohydrate intake and an increase in the consumption of fats.”
If you simply don’t believe the above is true (ie. you think surely fat is bad for us and I’m having a delusion) I recommend the well-researched book by Nina Teicholz “The Big Fat Surprise”.
Author: Eleanor (Ellie) Stein MD FRCP(C)
I am a psychiatrist with a small private practice in Calgary and am an assistant clinical professor in the faculty of medicine at the University of Calgary. Since 2000, I have worked with over 1000 patients, all with ME/CFS, FM and ES. My passion for this field comes from my own struggle with these diseases, my desire to improve my health and then pass on what I learn. My goal is for every patient in Canada to have access to respectful, effective health care within the publicly funded system. If you are looking for help and resources to help combat ME/CFS, FM and ES, see my guides and webinars.