Scientific studies show the connection between a high-fat diet and heart disease

The Verdict [Misleading]
It is misleading to claim that there is no link between a high-fat diet and cardiovascular disease.

The claim

A clip circulating on Facebook (archived here) claims that “zero studies actually prove that a high-fat diet causes heart disease.”

So far, it has been viewed by more than 38,000 users and has received more than 1,000 likes.

Similar statements have appeared on other platforms. In 2020, another post (archived here) claimed there is no “real evidence to support the idea that saturated fat consumption causes cardiovascular disease.”

Although the link between a high-fat diet and cardiovascular diseases, including heart disease, is complex, claiming that no studies prove a high-fat diet causes heart disease omits important context.

In fact

Cardiovascular disease (CVD) is a general term for conditions affecting the heart or blood vessels, including coronary heart disease, stroke, and rheumatic heart disease.

According to the World Health Organization (WHO), it is the leading cause of death worldwide, responsible for an estimated 17.9 million deaths annually.

The U.K.’s National Health Service says risk factors include genetics, age, smoking, physical inactivity, obesity, diabetes, high cholesterol, and high blood pressure.

According to the U.S. National Institutes of Health (NIH), diet can contribute to conditions like high cholesterol and obesity, increasing overall risk.

Fats also influence cholesterol, inflammation, and heart function. There are four types of fats — saturated fats (SFAs), trans fats, monounsaturated fats (MUFAs), and polyunsaturated fats (PUFAs).

While no single study may prove a direct cause-and-effect relationship, significant evidence shows certain types of fats, particularly SFA and trans fats, are associated with an increased risk of heart disease.

For example, a 2015 study published in The American Journal of Clinical Nutrition found that higher intakes of SFAs and trans fats were associated with an 81 percent and 67 percent increased risk of CVD, respectively.

The study also found that higher PUFA and MUFA intakes were associated with a lower risk of cardiovascular death, meaning that increased levels of these fats corresponded to reduced all-cause mortality.

Replacing SFAs with MUFAs or PUFAs, or trans fats with MUFAs, was linked to a lower risk of CVD. A 2019 review published in Advances in Nutrition supports these findings.

Studies, including a 2017 randomized controlled trial published in the research journal PLOS ONE, show that diets high in SFAs and trans fats raise LDL (low-density lipoprotein) cholesterol levels, which can lead to plaque buildup in the arteries and increase the risk of cardiovascular disease.

Both SFAs and trans fats raise LDL, but trans fats are more strongly linked to a higher risk of cardiovascular disease, according to a 2022 review published in the American Journal of Preventive Cardiology.

On the other hand, a diet rich in PUFAs and MUFAs, as stated by the American Heart Association, can help lower LDL cholesterol, and different clinical trials have shown that replacing SFAs with PUFAs reduces the incidence of CVD.

There is still no consensus on the exact extent to which SFA intake should be reduced. A 2020 study published in Nutrients, an international peer-reviewed journal, highlighted that trials from the 1960s to the 1980s focused solely on reducing SFA intake.

While these studies successfully lowered serum cholesterol levels, they did not lead to a decrease in the incidence of myocardial infarction or deaths from coronary artery disease. In contrast, more recent studies, such as the Diet Reinfarction Study, the Lyon Heart Study, and the PREDIMED study, have shown that the Mediterranean diet, which is rich in MUFAs, was more effective in preventing CVD and reducing coronary artery disease-related mortality compared to low-fat, low-cholesterol diets.

Furthermore, it is important to note that there are nine calories in every gram of fat, regardless of the type, and consuming high levels of calories from any source can lead to weight gain or obesity, which is also a risk factor for CVD.

Obese individuals have a 50 percent to 100 percent higher risk of death from all causes compared to those with a normal weight, with most of the increased risk attributed to CVD, according to an article in the European Health Journal.

The verdict

It is misleading to claim that there is no link between a high-fat diet and cardiovascular disease. Scientific research demonstrates that diets high in SAFs and trans fats increase the risk of CVD. Additionally, consuming high levels of any type of fat can lead to weight gain and obesity, which is a major risk factor for CVDs.

This article is written by Klara Širovnik and republished from Logically Facts. Read the original article here.