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Lean, unprocessed red meat part of a heart-healthy diet - and may help with weight loss
It's getting better, but I still have patients who believe that red meat is bad for them, and that if they want to eat healthier, they have to give up all red meat.

Mushrooms vs. Meat
I love mushrooms. With only about 15 calories per cup, they're a good source of fiber and are also a good source of Vitamin D, selenium, and folate (especially important for women of child-bearing age). The best part? They're cheaper than the same amount of beef (for an upcoming recipe I paid $1.50 for 4 ounces of crimini mushrooms and $1.99 for the same amount of 90% lean ground beef) with just as much umami flavor.

Will eating more vegetables reduce the risk associated with red meat?
The research is quite clear that red meat is not something you should be eating every day. Too much red meat has been implicated in a greater risk of developing colon cancer, breast cancer, heart disease and diabetes, and an overall greater risk of death from any cause.


 

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When questionable research still proves something



pork chops with garlic sauce - click for recipe!

My Health & Nutrition Bites are intended to share with you current, relevant health and nutrition research, explaining why it's important and how you can apply the results to your life. I look for randomized, controlled trials or large prospective studies and I almost never report on research in animals.

On a few occasions I've reported on lower quality research, especially when that research has generated some media interest. I want you to know what to look for so you can better evaluate the research for yourself.

On the other hand, sometimes that poor-quality research does prove something - just not what the authors thought they were proving.

In the September issue of the British Journal of Nutrition a team of Australian researchers published an article entitled "Effects of Mediterranean diet supplemented with lean pork on blood pressure and markers of cardiovascular risk: findings from the MedPork trial" (2019; 122:873-883).

The authors begin by noting that a Mediterranean diet has been recognized as contributing to lower rates of heart disease as well as improved blood pressures, cholesterol scores, and atherosclerosis, but a previous study of older Australian's experiences with adhering to a Mediterranean-style diet found that the participants had a difficult time with the red meat restrictions.

To get one point in your Mediterranean Diet score, you must consume less than 3.25 ounces of land animal protein (chicken, pork, beef, or lamb) per day on average, and most guidelines recommend no more than two 4-ounce servings of red meat per month. In this context, beef, pork, and lamb are all considered red meat.

Their study recruited 31 men and women between 45 and 80 who were at higher risk of heart disease due to at least two known risk factors such as high blood pressure, Body Mass Index over 25, poor cholesterol scores, or a family history of heart disease or diabetes. Those with active diabetes were excluded from the study.

The study was split into three phases: the participants were randomly assigned to follow one of two different diets, either Low Fat or a modified Mediterranean Diet, for an initial 8-week period, followed by an 8-week washout period during with they returned to their usual diets. Then for an additional 8 weeks they followed the other diet.

For the Low Fat diet the participants were instructed to replace all higher-fat foods such as oil, butter, higher-fat meats, and full-fat dairy products with low fat alternatives. No more than 20 milliliters (about 4 teaspoons) of oil and the same amount of butter or margarine was permitted.

The Mediterranean Diet (MedPork) was a fairly standard Mediterranean-style diet that included at least 3 3.5-ounce servings of fish per week as well as 2-3 servings of pork per week, no more than 1 serving of red (non-pork) meat per week, and less than about 3 servings of poultry per week, for a total of no more than about 14 ounces of land animal protein per week, or about 4 servings.

The authors did blood tests on the participants at the beginning and end of each phase and compared blood pressure scores, cholesterol scores, and other metabolic scores. The participants were not instructed to cut calories but only to modify their diets in accordance with each diet's guidelines. Regular visits with dietitians helped the participants stay on track, and regular diet surveys measured how well they stuck with their assigned diet.

Unsurprisingly, the Low Fat diet led to greater weight loss than the MedPork diet, but there were otherwise no differences between the two diets in blood pressures, insulin, glucose, or cholesterol scores: both improved blood pressure scores by about the same amount with no changes in the other scores.

What this means for you

The authors admit that their MedPork diet means that instead of consuming only one serving of red meat per week, the participants were consuming at least 3 and possibly 4 servings of red meat per week. It's no surprise that their modified Mediterranean Diet had no greater effects on blood pressures and other metabolic scores than the Low Fat diet.

The authors assert that because "the MedPork and LF interventions led to similar improvements across blood pressure measures. This indicates that the MedPork intervention has a similar cardiovascular risk profile to a LF diet and can be adhered to by an Australian population at risk of CVD." The suggest that pork should be considered for "future dietary recommendations" at the national level.

First of all, a low fat diet is no longer considered a good idea for improving heart health, so comparing a variation of a Mediterranean Diet to a low fat diet is like comparing it to a diet based on daily McDonald's intake: we already know most any Mediterranean-style diet that's low in processed foods, high in whole grains, legumes, and nuts, and increased consumption of monounsaturated fats (olive oil) is going to yield healthier results. Asserting that a modified Mediterranean-style diet is as good as a low-fat diet is not an impressive result.

Second, this study was funded by the Pork Cooperative Research Centre, who has a vested interest in getting Australians to choose pork as their red meat instead of beef or lamb. Research like this is so clearly biased that the British Journal of Nutrition should be ashamed of itself for publishing it.

Finally, here's what the authors of this study inadvertently proved: that even when the participants consumed far more red meat than they should, a Mediterranean-style diet (with extra red meat) still improved Australians' Mediterranean Diet score by at least two points, which we've seen can improve all-cause mortality by as much as 25%.

The take-home message here is that a Mediterranean-style diet need not be a perfect 9 points: as my wife likes to say, "perfect is the enemy of better." It's pretty easy to improve your Mediterranean Diet score by two points - it can be as small a change as having a peanut butter and jelly sandwich on whole grain bread every day for lunch. Take the Mediterranean Diet Score quiz to find out your Mediterranean Diet score - and get ideas for improving your score.

First posted: December 4, 2019