A new study from McMaster University in Hamilton/Ont. suggests that we eat more fat, fruit and vegetables. The study followed 135,000 people in 18 countries for 7 ½ years. The prospective cohort study (Prospective Urban Rural Epidemiology [PURE]) from McMaster University has a lot of strength. The number of participants and the length of the observation period make it statistically very powerful. The researchers charted people’s meals and associated this with strokes, heart attacks and deaths that occurred in this population. The Lancet published these findings.
Fat intake protects against strokes and lowers all cause mortality
The first study was regarding fat intake and the development of strokes, heart attacks and deaths in general. When researchers observed the effects of carb intake by comparing the highest carb quintile to the lowest carb quintile, the higher carbohydrate diet (low fat/high carb diet) had a 28% higher mortality rate. This does not fit into the old hypothesis that a fatty diet would be associated with a higher mortality and lower fat intake would be protective. Next the authors found that regardless of what fat people consumed, the mortality was 23% lower. They observed the effects of higher versus lower consumption.
Subtypes of fat
The team also measured the effects of subtypes of fats. Saturated fat reduced mortality by 14%, monounsaturated fat (like olive oil) reduced mortality by 19% and polyunsaturated fat reduced mortality by 20%. Higher consumption of saturated fat caused 21% less strokes comparing the findings to people eating lower amounts of saturated fats. It is of note that heart attacks and deaths from heart attacks were not associated with any fat consumption. This is a key finding, which finally puts the old diet rules from the 1980’s (low fat/high carb diet) in the trashcan!
Fruit, vegetables and legumes make you live longer
Researchers also investigated the effect of fruit, vegetables and legumes in a second publication in the Lancet. Over the 7 ½ hears of observation 4784 heart attacks, 1649 cardiovascular deaths, and 5796 total deaths were observed. Higher intake of fruit, vegetables and legumes shwed an association with less mortality from heart attacks, strokes and other diseases. The investigators looked again at highest versus lowest quintiles of fruit, vegetables and legumes intake. They found that higher intake of fruit, vegetables and legumes reduced cardiovascular diseases by 10%. There was a reduction of strokes by 8%, and cardiovascular mortality was down by 27%. Non-cardiovascular mortality showed a reduction by 16% and total mortality by 19%. When people consumed three to four servings of fruit, vegetables and legumes per day the mortality was lowest; it went down by 22%. The conclusion is to eat more fat, fruit and vegetables.
The effects of fruit or vegetables
What did fruit or vegetables do separately? The consumption of fruit reduced the risk of heart attacks; it also reduced non-cardiovascular mortality and total mortality (from all causes). The intake of legumes reduced the risk from non-cardiovascular deaths and reduced total mortality. Comparing raw vegetables with cooked vegetables showed that raw vegetable consumption reduced mortality strongly while cooked vegetable consumption reduced mortality only modestly. Consumption of three to four servings per day (equivalent to 375–500 g/day) appeared to be the optimal dose of fruit, vegetables and legumes. Higher intake did not lead to more protection.
The recommendation of the authors is that a diet consisting of 50 to 55% of complex carbohydrates (fruit, vegetables and legumes), 20% of healthy fats and 25% to 30% of protein would reduce mortality to the lowest point. With regard to fat there is room to increase fats to 30% or 40%. It has to be emphasized that the key is to not increase the carbohydrate intake. There is no room for adding refined carbohydrates like rice, potatoes, bread or other starchy foods. These refined carb foods will increase the rates of heart attacks and strokes and increase the all-cause mortalities as well, including diabetes, cancer and other diseases. This study confirms what other smaller studies have stated in the last 20 years. It is safe to eat more saturated fat, and it confirms that the old teaching from the 1980’s –namely the low fat/high carb diet- was wrong.