Low fat diets are not as healthy as first seems.

• Low fat diets have long been seen as the way for many of us to maintain a healthy life style, manage our weight and extend our lives.
• New research now suggests this type of diet may not be the one to follow and actually shortens our life.
• The study suggests that a low-fat diet may mean that roughly a quarter of us who follow such a diet are at risk of earlier death.

Contradictory evidence regarding nutrition is nothing new but there has been accepted wisdom from a number of studies that suggests a healthy diet low in fats, saturated ones in particular, is good for you. Research at McMaster University in Ontario, Canada throws this recommendation on its head. The study is reported in the medical journal ‘The Lancet’. It was presented at the European Society of Cardiology Congress in Barcelona, Spain.

Data from 135,000 adults in 18 countries was collected on their eating patterns and death rates. It appears if the report is accurate that the analysis points to the following conclusions:- if you cut your saturated fat intake to a point where it was only 3% of your total calories, then the death rate increased by 13%. Higher levels of consumption of fats of all kinds reduced the overall risk of death by 23%, stroke risk by 18% and non-heart related mortality by 30%.

Incidentally, foods rich in saturated fats include meat, lard, cream, butter and cheese. The current guidance in the UK is that men should eat no more than 30g and for women, 20g of fat daily.

Such findings appear to be in line with an earlier study about consumption of fat and mortality not that long ago which came to similar findings.

Of interest were those diets high in carbohydrates which accounted for 77% of calorie intake. These were associated with a 28% greater risk of death but did not impact the rate of heart attack or stroke. The implication here was that diets high in carbohydrates put you at a greater risk of death.

In this study, different quintiles of people were compared. Those who were in the top fifth of carbohydrate and fat consumers were compared with the quintile at the bottom end of consumption over 7.4 years. The participants had a wide age range from 35 to 70. The countries were also divided into levels of income: low, middle and high.

Across the world, the average diet is 61.2% carbohydrates, 23.5% fats, including 8% saturated fats, and 15.2% protein. Carbohydrate intake was highest in China, South Asia and Africa, while people who ate the most fat lived in North America, Europe, the Middle East and South-East Asia.

The Lead scientist, Dr Mahshid Dehghan, from McMaster University in Canada, claimed:

‘The current focus on promoting low-fat diets ignores the fact that most people’s diets in low and middle income countries are very high in carbohydrates, which seem to be linked to worse health outcomes.’

‘In low and middle-income countries, where diets sometimes consist of more than 65% of energy from carbohydrates, guidelines should refocus their attention towards reducing carbohydrate intake, instead of focusing on reducing fats.’

‘The best diets will include a balance of carbohydrates and fats – approximately 50-55% carbohydrates and around 35% total fat, including both saturated and unsaturated fats.’

Researcher Dr Andrew Mente, also from McMaster University, said:

“Our data suggests that low fat diets put populations at increased risk for cardiovascular disease. Loosening the restriction on total fat and saturated fat and imposing limits on carbohydrates when high to reduce intake to moderate levels would be optimal.”