By Steve Blechman

A most recent study published in the October 1, 2019 issue of the Annals of Internal Medicine concluded that the evidence isn’t strong enough to recommend people reduce their intake of red meat or processed meats. The study and researchers were criticized by prominent U.S. scientists and researchers. The researchers of the study reported on four reviews examining the links and association between red meat, cardiovascular disease and cancer risk! The researchers found that increased risk of eating meat is small. This is an extremely controversial study, and will no doubt confuse the public. Public health officials have recommended in the past to limit consumption of red meat and processed meats because of concerns that it is linked to heart disease and cancer as well as other diseases. In an article published in The New York Times, The Times spoke to researchers at Harvard University that reported the results of the study, and acknowledged that the study can, “harm the credibility of nutrition science and erode the public trust on scientific research.”

The shortcoming of the study was that it was an observational study where researchers questioned what people eat and link cardiovascular health and cancer risk. People don’t always remember what they ate. Observational studies don’t prove cause and effect. The gold standard when it comes to scientific research studies are randomized clinical trials.

So, is red meat good for you based on this latest observational study, when the research doesn’t prove so? It was mentioned in the media that the lead author of the study had done work for the food industry, which some feel can be a conflict of interest, but the researchers reported at the end of the study no conflicts of interest, and without outside funding.

What I have learned reviewing the research over the years is that you could always design a study to prove a point! For instance, if the study were done with all meat, not just red meat but white meat from poultry and whole eggs, would the outcome have been different? Research has shown arachidonic acid, a polyunsaturated fat, is essential for normal growth and development in the human body. Too much arachidonic acid in the diet has been strongly linked to inflammation and a higher risk of heart disease, cancer and other diseases. The richest dietary source of arachidonic acid is white meat such as poultry (i.e., chicken and turkey). The second highest amounts of arachidonic acids in the diet are whole eggs found in the yolk!  Beef is the third largest contributor of arachidonic acid, according to the National Health and Nutrition Examination Survey (NHANES). Research has shown that the amount of arachidonic acid found in just one whole egg a day raises arachidonic acid in the blood. A recent study in the American Journal of Clinical Nutrition reported that in a randomized study in 113 healthy adults (aged 21-65), white meat resulted in the same increase of LDL (bad cholesterol) and total cholesterol as red meat. There was no benefit on LDL cholesterol consuming white meat over red meat. This is a very important study because people with high risk of cardiovascular disease often think that white meat is healthier and better for lowering LDL cholesterol than red meat! How many people do you know that think white meat is healthier than red meat for the prevention of cardiovascular disease? In fact, white meat might be worse than red meat because of the amount of arachidonic acid in white meat such as poultry (i.e., chicken and turkey). Duck actually has the highest levels of arachidonic acid!

This year, U.S. News & World Report (January 2nd, 2019) selected the Mediterranean diet as the best overall diet and healthiest diet for 2019. It was also rated the best diet for preventing heart disease and diabetes. These results were based on a panel of 23 experts, and 41 diets based on the scientific literature. The expert panel consisted of the country’s top nutrition experts and physicians specializing in weight loss, diabetes and cardiovascular disease. The Mediterranean diet is low in arachidonic acid and rich in healthy fats such as monounsaturated fats found in extra-virgin olive oil (EVOO), nuts and omega-3 fatty acids from fish, which has been shown to lower the risk of inflammation, heart disease, cancer, diabetes and obesity, and other degenerative diseases.

A recent study showed that the Mediterranean style diet may also lower women’s stroke risk, which was reported by the American Heart Association’s journal Stroke in October 2018. Another recent Harvard study published in the Journal of the American Medical Association (JAMA) on December 7, 2018, found a 25% reduction in cardiovascular risk on the Mediterranean diet! Finally, a recent study published in the International Journal of Cardiology on November 27, 2018 reported that the cholesterol-lowering statin drugs worked best when combined with a Mediterranean diet compared to statin drugs alone! Lowering inflammation and LDL (bad cholesterol) seems to be the likely synergistic benefit of combining the Mediterranean diet and statin drugs in people with cardiovascular disease and lowering mortality risk.

The Mediterranean diet contains healthy fats from monounsaturated fats and is low in bad fats. Twenty-five years ago, nutritionists discouraged nut consumption because of their high fat content. Mountains of evidence show that nuts are a healthy food that reduce the risk of cardiovascular disease, cancer and all-cause mortality. A meta-analysis that combined the results of 20 studies involving more than 819,000 people, led by Dagfinn Aune from the Imperial College London, found that consuming 28 grams of nuts per day was linked to a reduced risk of coronary heart disease (29%), stroke (70%), cardiovascular disease (21%), total cancer risk (15%) and all-cause mortality (22%). Adding nut consumption to your daily diet can have a marked improvement on your health and prevention of disease (BMC Medicine, 2016).

A most recent study published in the prestigious Journal of Internal Medicine (July 17, 2018) found that consumption of fish, and long-chain omega-3 fatty acids, was associated with low risk of early death. According to an article in ScienceDaily (July 18, 2018), “…in the study, 240,729 men and 180,580 women were followed for 16 years. 54,230 men and 30,882 women died. Higher fish and long-chain omega-3 fatty acid intakes were significantly associated with lower total mortality. Comparing the highest with lowest quintiles of fish intake, men had 9% lower total mortality, 10% lower cardiovascular disease mortality, while women had 8% lower total mortality, 10% lower cardiovascular disease mortality and 38% lower Alzheimer’s disease mortality.” Consuming salmon twice a week improves the blood fat profile in overweight men and women— according to a study in the journal Nutrition Research (2016). The benefits were dose dependent— eating more fish triggered greater benefits in blood fats. The study found that salmon consumption reduced blood triglyceride (blood fat) and increased HDL cholesterol levels (the good cholesterol) and benefited the size of lipoprotein molecules, which is important for reducing the risk of coronary artery disease.

Regular salmon consumption is part of a heart-healthy diet. Ocean and wild fish are preferable over farmed fish. They are richer in omega-3 polyunsaturated fatty acids. For example, farmed tilapia is not a healthy fish because it is very low in omega-3 fatty acids and rich in arachidonic acid, a polyunsaturated fatty acid that can increase inflammation and is linked to a higher risk of cardiovascular disease, cancer, metabolic syndrome and insulin resistance.

So, are you confused by the research presented in the media? The Mediterranean diet has been shown to be low in arachidonic acid and rich in omega-3 fatty acids and monounsaturated fatty acids, which have been shown to lower inflammation and lower the risk for cardiovascular disease, cancer and other degenerative diseases.

The bottom line is don’t believe everything that you read in the media on the latest scientific studies. Like I said before, the gold standard for medical research and evidence in scientific research conclusions is based on randomized double-blind clinical trials, and not observational studies! The most recent Annals of Internal Medicine study on red meat is an observational study and does not prove that red meat is not bad for you when it comes to heart disease and cancer!

References:

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