Not Everyone Gets a Mortality Benefit From Reducing Saturated Fats, Study Says

 Will your competent? doctor do the proper testing on you? NO? Just regular incompetence as usual? Are you at low baseline cardiovascular risk, or not?

Your doctor has informed you of the benefits of dairy fat, right? 

Dairy fat from milk, butter, and cheese could actually PREVENT a heart attack September 2021 

Oh no, your doctor is totally fucking incompetent? And you're paying them?

Not Everyone Gets a Mortality Benefit From Reducing Saturated Fats, Study Says

Key Takeaways

• A meta-analysis showed that reducing saturated fat intake was associated with reduced mortality, albeit only in high-risk individuals.
• For people at low to intermediate cardiovascular risk, cutting or replacing saturated fat intake offered little or no benefit over 5 years.
• The study adds more evidence to the ongoing controversy about dietary saturated fats.

Decades-old fears of heart risks from eating saturated fats appeared to have been overblown for many individuals, according to a meta-analysis of randomized trials.

Across 17 studies, reduced saturated fat intake did not significantly tip outcomes towards harm or benefit for endpoints including all-cause mortality, cardiovascular mortality, myocardial infarction (MI), and stroke, with the evidence providing low to moderate certainty that reduced saturated fats leaned towards benefit, reported Bradley Johnston, PhD, of Texas A&M University in College Station, and colleagues.

For people at low baseline cardiovascular risk, in particular, there was virtually no clinically relevant 5-year benefit from eating fewer saturated fats.

Some cardiovascular benefits emerged only in high-risk people. "Important absolute reductions" in individual outcomes -- ranging from six fewer deaths per 1,000 people to 12 fewer MIs per 1,000 -- were reported, albeit with low to moderate certainty in the meta-analysis published in the Annals of Internal Medicine.

The study thus marks another challenge to traditional thinking that dietary saturated fats must be generally bad because they increase cholesterol, and therefore heart disease.

"The findings of this review align with the current emerging recognition that dietary SFAs [saturated fatty acids] per se are unlikely deleterious for cardiometabolic health for the general population but may be deleterious for persons at high risk for cardiovascular events," noted Ramon Estruch, MD, PhD, and Rosa Lamuela-Raventós, DPharm, PhD, both of the University of Barcelona in Spain, in an accompanying editorial.

Estruch and Lamuela-Raventós cited prior work that showed important differences among the various saturated fats; in some studies, certain saturated fats even appeared beneficial for health.

"Evidence indicates that medium-chain SFAs may improve lipid profiles, enhance glucose homeostasis, and aid weight management by increasing high-density lipoprotein cholesterol without significantly increasing low-density lipoprotein [LDL] cholesterol," the duo wrote. "Key sources include coconut oil, palm kernel oil, and dairy products."

"In fact, maintaining a high intake of polyunsaturated and monounsaturated fatty acids, along with the consumption of short-, medium-, and very long-chain SFAs, as well as odd-chain SFAs, may confer salutary benefits within the context of an overall healthy and balanced diet," Estruch and Lamuela-Raventós concluded.

Indeed, the final 2025-2030 Dietary Guidelines for Americans, not yet released, are anticipated to encourage eating more foods high in saturated fats under HHS Secretary Robert F. Kennedy Jr.'s "Make American Healthy Again" initiative.

Many consider this to be going against the established science, however. As they stand, most dietary recommendations still advocate for saturated fat intake of less than 10% of total daily caloric intake -- with some groups suggesting going down to around 5%.

Johnston's team suggested that the guidelines got there due to studies relying on surrogate markers.

"Beginning in the 1950s, controlled metabolic studies in humans have consistently shown that dietary fat composition has a substantial effect on total and LDL-C [cholesterol]," they noted. "Although the link between dietary SFA and circulating LDL-C is strong, the reliance on surrogate outcomes to inform nutritional guidance has been the topic of critique."

Johnston and colleagues' meta-analysis covered 17 trials, published from 1965 to 2006, in which a dietary intervention was intended to be tested for at least 2 years. Altogether, they had over 66,000 participants, and were conducted mostly in North America and Europe. Average age ranged from 46 to 66 years across studies.

Overall, the authors found with low to moderate certainty that reducing saturated fat intake may result in a reduction in all-cause mortality (risk ratio [RR] 0.96, 95% CI 0.88-1.06), cardiovascular mortality (RR 0.93, 95% CI 0.77-1.11), nonfatal MI (RR 0.86, 95% CI 0.70-1.06), and fatal and nonfatal stroke (RR 0.83, 95% CI 0.58-1.19).

Regarding the risk of nonfatal MI for high-risk people, there was a particularly strong effect from replacing saturated fats with polyunsaturated fatty acids (RR 0.75, 95% CI 0.58-0.99) rather than reducing saturated fats alone, Johnston and colleagues reported.

They acknowledged that the evidence was sparse for replacing saturated fats with monounsaturated fats or proteins. "Trials varied considerably in their efficacy in reducing saturated fat intake and in their replacement macronutrients and concomitant dietary interventions, and new trials are needed to clarify uncertainty," they wrote.

In addition, they said the meta-analysis included trials that were arguably outdated -- many conducted before the introduction of statins -- and often lacked comprehensive dietary intake assessments precluding more detailed analyses of fatty acid consumption and cardiovascular risk.