PHL chemists point out errors amid warning on saturated fats, coconut oil

The Integrated Chemists of the Philippines (ICP) on Wednesday said there has been "experimental errors and biases" on the hypothesis that coconut oil, being a saturated fat, raises bad cholesterol.

This came after the American Heart Association (AHA) pointed out that coconut oil is raising low-density lipoprotein (LDL) about as much as other oils high in fat like butter, beef and palm oil in seven out of seven studies reviewed by the AHA for its advisory published in the journal Circulation.

According to Fabian Dayrit, ICP president, the recommendation "to decrease saturated fat effectively means an increase in unsaturated fat in the diet."

"The actual result has been an increase in omega-6 fats and a high omega-6 to omega-3 fat ratio. This unhealthy ratio has been linked to heart disease, the very disease that the AHA wants to target, as well as cancer and inflammatory diseases," Dayrit said.

Dayrit also said the warnings against saturated fats, especially coconut oil, was based on the study by Ancel Keys in 1950.

"The Keys hypothesis, generally known as the saturated fat-cholesterol-heart disease hypothesis, states that saturated fats raise serum cholesterol which in turn increases the risk for heart disease. Although the saturated fats that are most often studied are animal fats, coconut oil is often included in this warning because it is a saturated fat," Dayrit said.

Dayrit noted that Keys wanted to compare the effects of feeding monounsaturated and polyunsaturated fats versus saturated fats on serum cholesterol.

He added that Keys used corn oil, olive oil, cottonseed oil, safflower oil, and sardine oil for sources of unsaturated fats while he used butterfat, margarine and hydrogenated coconut oil (HydrolÔ) in saturated fats.

"The use of hydrogenated fats – margarine and Hydrol – in this feeding study casts doubt on the validity of the conclusions of this work regarding the effects of coconut oil. It was already known in the 1920s that hydrogenation of vegetable oils produced trans fats (Hilditch & Vidyarthi, 1929)," Dayrit said in his article.

"In 1957, the same year when both Keys' papers came out, it was reported that trans fats were deposited in various human tissues, such as adipose tissues, liver, aortic tissue, and atheroma of those who died of atherosclerosis (Johnston, Johnson, Kummerow, 1957)," he added.

Dayrit pointed out "the increase in serum cholesterol that Keys observed may have been due to the trans fats in margarine and hydrogenated coconut oil and this would make his conclusions invalid."

Seven Countries Study

Dayrit also took note that the Seven Countries Study, which aimed to identify dietary and lifestyle factors in apparently healthy middle-aged men that contributed to coronary heart disease (CHD).

He said the study which was started in 1956 and published in 1986, is not a representative study:

This study does not represent all types of oils and for all groups of people.

The beneficial oil claimed in the Seven Countries Study was olive oil and it should be compared only to the other fats and oils that were consumed, which was mainly animal fat.

This study assumed that all saturated fats have the same properties regardless of chain length. This assumption is not valid given what is known today regarding the individual properties of saturated fatty acids.

Dayrit questioned that coconut oil was included in health warnings on heart disease even if it was not a significant part of the diet in Europe and United States.

The Minnesota Coronary Survey (MCS) from 1968 to 1973, he added, sought to test whether replacing saturated fat (animal fat, margarines and shortenings) with vegetable oil that is rich in linoleic acid (mainly corn oil) will reduce all-cause deaths, CHD in particular, by lowering serum cholesterol.

The main conclusion of the study was that a high linoleic acid diet effectively lowers serum cholesterol. However, this increases the risk of CHD.

"The results of the MCS study did not give the expected results and directly contradicted the conclusions of the Seven Countries Study which Keys had published a few years earlier in 1986," Dayrit said.

"Despite its widespread adoption, the saturated fat-cholesterol-heart disease hypothesis has been shown to be incorrect. Ancel Keys committed a number of errors and was unable to unambiguously demonstrate a causal link for the role of saturated fat in heart disease," Dayrit added. — BAP, GMA News