New Findings on Processed Oils and Heart Health

Recent research has indicated that some processed vegetable and seed oils, often found in common products like margarine and baked goods, may not pose as much of a threat to heart health as previously believed.

A six-week study involving 47 healthy adults, conducted by researchers from King’s College London and Maastricht University, revealed no significant changes in health markers when participants consumed muffins and spreads made with palm-enriched fat or fully hydrogenated seed oil (referred to as ‘interesterified’ or IE fat).

The researchers assessed participants’ cholesterol, blood sugar, liver fat, and inflammation levels, ultimately finding that overall heart health markers remained steady regardless of the type of fat consumed.

It’s worth noting that even low-calorie processed foods may lead to weight gain and decreased testosterone levels in men, as suggested by other research.

Short-term results shared in the American Journal of Clinical Nutrition suggest that the two kinds of processed oils yield similar outcomes in healthy individuals.

By processing vegetable oils to create IE fats that mimic butter or lard, food producers can enhance texture without incorporating trans fats, which are known to elevate heart disease risks. These fats often appear as “vegetable oil” or “palm oil” on ingredient labels.

Wendy Hall, a professor of nutritional science at King’s College London and the study’s lead author, commented that the findings imply IE fats used in the food industry can fit into a healthy diet. She emphasized that not every industrial processing method is harmful, as is frequently suggested in discussions about ultra-processed foods.

While advising caution, Hall noted that the nutritional profile of foods is essential to consider rather than merely the processing method. However, it’s important to recognize that this study is short-term and primarily involved healthy participants.

“Six weeks is a sufficient duration to observe short-term cholesterol changes,” Hall mentioned, but she stressed the necessity for long-term studies to thoroughly understand the risks associated with heart disease.

Experts agree that more extensive research is required to evaluate the long-term implications of these fats on heart health.

Dr. Steven Goldberg, chief medical officer at HealthTrackRx in Texas, described this study as one of the first well-controlled investigations comparing these commonly used IE fats. He noted that these alternative fats appear metabolically neutral when consumed in realistic amounts, aligning with prior findings that stearic acid does not significantly alter cholesterol levels.

Goldberg pointed out that while IE fats share the same fatty acids found in natural fats, their structural differences do influence digestion and metabolism without presenting the same cardiovascular risks as trans fats.

That said, he cautioned that the term “safe” should be approached with care. The six-week timeframe is insufficient for determining long-term effects, particularly in populations at higher risk for heart conditions.

“As with all saturated fats, moderation is crucial, especially within a diet that includes plenty of unsaturated oils, fruits, vegetables, and whole grains,” he advised, noting that it’s the biochemical effects that ultimately matter.

Dr. Sam Setare, director of cardiology and cardiovascular function at the Beverly Hills Cardiovascular Longevity Institute, found these discoveries promising. He noted that IE fats, being used as an alternative to trans fats, have been under-researched in human subjects. Still, he echoed the need for careful interpretation of the results.

Setare emphasized that labeling these fats as ‘heart-healthy’ right now may be premature, although the findings challenge the notion that all processed fats are inherently damaging to heart health.

Interestingly, previous studies on IE fats have yielded varied findings. Some animal and infant research indicated that the structural variations of these fats can influence how fats are absorbed and how cholesterol is processed, but results in adult studies remain mixed, likely dependent on fat types and quantities consumed.

Although the study did receive partial funding from the Malaysian Palm Oil Board, the researchers clarified that the investigation was independently conducted and peer-reviewed.