A British cardiologist says it’s time to “shatter the myth of the role of saturated fat in heart disease,” noting that since we started following advice to remove it from our diet, cardiovascular risk has increased.
Writing in this week’s online issue of British medical journal Aseem Malhotra, Registrar Specialist in Interventional Cardiology at Croydon University Hospital, London, also says the government’s obsession with lowering total cholesterol has led to millions of people being over-medicated with statins, when the real problem isn’t It’s not cholesterol but a more complex triad of lipid abnormalities called “atherogenic dyslipidemia”.
He describes how the landmark “Seven Countries” study from the 1970s showed links between rates of coronary heart disease and cholesterol levels, and linked this to the energy levels of saturated fat. But without establishing whether these factors actually caused heart disease, governments have issued guidelines telling us to reduce fat intake to 30% of total calories and saturated fat to 10%.
In the meantime, “recent prospective cohort studies have confirmed no significant association between saturated fat intake and cardiovascular risk” and “instead, saturated fat has been shown to be protective,” he adds. -he.
Dr Malhotra points to the sugar. When you remove fat from food, it tastes worse, so the food industry has replaced saturated fat with added sugar.
Now, evidence is mounting showing that sugar may be an independent risk factor for metabolic syndrome (a group of conditions that includes high blood pressure, abnormal blood sugar levels, high triglycerides, low cholesterol, and high blood pressure). size important), which is known to lead to diabetes. and increased cardiovascular risks.
Another failure of the argument demonizing saturated fat is the idea that because it is high in energy, reducing it will reduce calorie intake. But, aside from the fact that food producers have replaced it with sugar, this argument faces growing evidence to support the theory that a “calorie is not a calorie” – where that energy comes from may be. determine the amount of energy consumed.
Fat has more energy per gram than protein and carbohydrate, but Dr. Malhotra cites studies which show that the body does not metabolize these nutrients in the same way; indeed, among weight loss diets comprising 90% fat, 90% protein and 90% carbohydrate, the greatest weight loss was recorded in the 90% fat group.
Over the past 30 years, he notes, Americans have reduced the proportion of energy intake from fat from 40% to 30%, but “obesity has exploded.”
Another major concern is where the saturated fat comes from. For example, dairy products are high in fat, but they also provide vitamin A and vitamin D and essential minerals, such as calcium and phosphorus. Low levels of vitamin D can be a major cause of high blood pressure and have also been linked to an increased risk of death from cardiovascular disease.
There is also some evidence that a fatty acid mainly found in dairy products is linked to higher levels of high density lipoproteins (the “good” cholesterol that helps fight heart disease), insulin resistance. reduced and other protective factors.
Meat is also a rich source of saturated fat, and although processed meat has been linked to an increased risk of coronary heart disease and type 2 diabetes (possibly due to its high nitrate and sodium content), this is not the case with red meat.
Statins, taken to lower total cholesterol, are now the second most commonly prescribed drug in the United States, thanks to the powerful influence of the Framingham heart study which, among other things, found total cholesterol to be a factor. risk of coronary heart disease.
But, says Dr Malhotra, take for example the UK, where 60 million statin prescriptions are filled each year, there is no evidence that they reduced cardiovascular deaths more than can be explained. by reducing smoking and life-saving. treatments like angioplasty.
And, he points out, although in the past, cardiovascular disease mostly happened on its own, today two-thirds of people who end up in hospital after a heart attack suffer. metabolic syndrome, while 75% of them have normal cholesterol levels.
More evidence, perhaps, that total cholesterol isn’t the culprit, he suggests.
The longer a drug is used by more and more patients, the more opportunities there are to compare what is happening in the general population with the results of the clinical trials that led to the drug’s approval.
In the case of statins, what emerges is a stark contrast between the results of the original clinical trials and the “real word” experience.
While clinical trials found that only 1 in 10,000 patients who received statins had a minor side effect (0.01%), a study of 150,000 patients prescribed by their GP showed that 20% had any effects. secondary “unacceptable” that they stopped taking them. Side effects included upset stomach, muscle pain, trouble sleeping and memory, and erectile dysfunction.
Dr Malhotra says the strongest evidence to support statins is to prevent second heart attacks, where patients are given the maximum dose, regardless of their total cholesterol levels. This is because statins are effective in stabilizing coronary plaques and reducing inflammation in blood vessels.
“The fact that no other cholesterol lowering drug has shown a benefit in terms of mortality supports the hypothesis that the benefits of statins are independent of their effects on cholesterol.”
Dr Malhotra advocates adopting a Mediterranean diet – it has been shown to be three times more effective in reducing cardiovascular death than statins. Even compared to a low fat diet, a recently published trial showed that in high risk groups, a Mediterranean diet reduced cardiovascular events.
A traditional Mediterranean diet is rich in olive oil, fruits, nuts, vegetables and grains, contains moderate amounts of fish and poultry, and low amounts of red and processed meats, dairy products and sweets. Wine is drunk in moderation and only with meals.
Dr Malhotra urges doctors to “embrace prevention as well as treatment.” Medications can relieve symptoms but they cannot change the “pathophysiology,” he says, and concludes:
“It’s time to shatter the myth of the role of saturated fat in heart disease and reverse the harms of dietary advice that has contributed to obesity.”
Update May 15, 2014 – The authors of the BMJ withdraw their statements on the side effects of statins.