KEY POINTS

  • Elevated blood cholesterol levels increase heart disease risk
  • It was believed that HDL offered protection against heart diseases
  • But new research pointed out that very high levels of HDL could still lead to heart attack

After a certain point, 'good' cholesterol can actually become a risk factor of heart attacks, according to a recent study.

It has been believed that high levels of HDL reduce the likelihood of heart attacks and experts have been advising people to consume lots of healthy fats including olive oil, fish, and nuts in order to raise HDL levels. But according to the new research, very high levels of good cholesterol could also be bad. Individuals with too much HDL levels could be at an increased risk of a heart attack.

Experts have always talked about cholesterol in terms of ‘good’ and ‘bad’.

HDL Vs LDL cholesterol:

The HDL (High-density lipoprotein) or good cholesterol is believed to clear away blood cholesterol in such a way that it is processed by the liver and is flushed from the body.

The LDL (Low-density lipoprotein) also known as bad cholesterol is responsible for waxy deposits or plaques in the arteries.

"It’s true that very low HDL isn’t a good thing, and the risk of a heart attack lowers as HDL rises. But we now know unusually high HDL in some people isn’t protective and is associated with an increased risk of heart attacks. It was a surprise when the research started to show this," Consultant cardiologist Dr. Laura Corr told Daily Mail.

The initial belief that HDL was all 'good,' comes from research carried out in the early 1990s which revealed that those with a higher HDL were at a lower heart attack risk. This finding led to a series of large trials that helped find drugs to artificially elevate HDL and harness the benefit. But these trials were not successful.

The drugs were not efficient in reducing the number of heart attacks and sometimes they have nasty side effects such as itching, skin flushing, nausea, heart problems, liver damage, and digestive discomfort.

A major analysis conducted in 2018 specifically examined the link between HDL and risk of heart attack and mortality. The experts at the Emory University School of Medicine, Atlanta studied nearly 6,000 patients, with an average age of 63.

Key Findings:

  • 13% had a heart attack or died from cardiovascular disease
  • More heart attacks were experienced in people with very low HDL (less than 1)
  • Surprisingly, people with very high HDL levels (>1.4) also experienced more heart attacks
  • Only those with HDL levels between this range had a lower risk of heart attack
  • The pattern remained the same irrespective of what the LDL cholesterol levels were, and whether or not they smoked or were diabetic

“Traditionally, doctors have told their patients that the higher your “good” cholesterol, the better. However, the results from this study and others suggest this may no longer be the case,” Cardiologist Dr. Marc Allard- Ratick, who led the study told Daily Mail.

Heart Attack
Pictured: Representative image of a man experiencing heart attack symptoms. Pexels