Proteins Link To Cardiovascular Disease

Here we go again with the conflicting information about health…I am just as frustrated by it as you are.

Recently an article from the New York Post came out with the headline “You might be eating an artery-damaging amount of protein for breakfast, new study warns”.

This is an example of what people find so frustrating about nutrition. In the span of 24 hours you can read one article that says that most people are undereating protein and need to be eating more and then read another article saying protein is damaging your arteries.

How do you know what is correct?

You probably know my stance on protein, it’s the one thing I think people should go out of their way to eat. I have written extensively about the benefits the research shows and what I have seen when working with clients.

Is this article from the New York Post true? Do we need to be concerned about protein and our heart health?

Let’s dive in a little bit more to see if we can decipher it.

The article is based on this study from Nature (Identification of a Leucine-Mediated Threshold Effect Governing Macrophage mTOR Signalling and Cardiovascular Risk, 2024). The study was done on humans (as opposed to our furry mice/rat friends) but only included 23 overweight men and women.

In the study they had participants consume 500 calories from a “high-protein” meal and a standard protein meal. The high-protein meal had 62 grams of protein, 9 grams of fat, and 41 grams of carbs. The standard protein meal contained 12.5 grams of protein, 9 grams of fat, and 91 grams of carbohydrates. In this part of the study the researchers used Boost Plus.

The researchers also fed participants a whole food meal. The high protein meal in this part of the study contained 25 grams of protein and the low protein meal contained 16 grams of protein.

The researchers found that consuming 62 grams of protein (from Boost Plus) as well as 25 grams of protein (from whole foods) resulted in reductions in the recycling of immune cells in participants’ cardiovascular systems.

What’s the problem with that?

The normal response by the body when these immune cells in the cardiovascular system become damaged is they get recycled by the body to clean them up. If these damaged immune cells don’t get cleaned up by the body they can promote the buildup of plaque in the arteries. This buildup of plaque is what leads to cardiovascular disease.

The main takeaway from this study is that if you consume 25g or more of protein it can lead to cardiovascular disease.

No bueno!

The researchers dug deeper to see if they could pinpoint what in the protein was causing the reduction of recycling of immune cells.

Protein is composed of a combination of amino acids. The researchers found that one of those amino acids, Leucine, correlated with the reduction in immune cell recycling. In other words the higher the Leucine content of the meal the more the recycling of the immune cells was inhibited.

If you are super nerdy like me you may have heard of Leucine before…if not that OK I will fill you in!

Leucine is a very important amino acid because it is the key amino acid needed to turn on the signal telling your body to build muscle. If you eat protein without enough Leucine your body won’t have enough of the building blocks to add muscle to your body.

So that’s a summary of the study that the New York Post article was based on, but how does this manifest practically? How would this research change recommendations?

Myself, and many others, have stated that people should be shooting for around 1 gram of protein per pound of body weight (or 2.2g per kilogram of body weight) to reap all the benefits from protein including gaining and maintaining muscle mass, recovery from exercise, and keeping you full and satisfied for longer so you don’t overeat.

For example, if you weigh 150 pounds (around 70 kilograms) you would need to eat 150 grams of protein a day.

If you eat three meals a day you would need to be eating 50 grams of protein at each meal in order to hit that number.

If we trust the conclusions from this study and are concerned about our cardiovascular health (who isn’t?) then we would need to eat no more than 25 grams of protein at a time to avoid suppressing immune cell recycling.

So let’s say we only can eat 20 grams at a meal (the study didn’t provide an exact amount of grams to eat, but let’s just theorize), that means we would need to eat 20 grams of protein seven to eight times a day in order to get to our target goal of 150 grams of protein per day.

Does that sound like a hassle?

It does to me!

We also need to think about the time frame when discussing processes in this body.

Here is an example that might be more familiar to people.

If you cut yourself you lose blood. We know losing blood is a bad thing because if we lose too much we are going to be in a world of trouble.

That said if it is just a small cut your body can recover from the cut and the bleeding usually stops in a couple minutes…crisis averted.

However if for some reason the bleeding doesn’t stop or you continuously get cut and lose more and more blood then that is an issue.

The chronic loss of blood is bad, an acute short term loss of blood is no big deal.

To tie this back to the topic at hand the study showed that immune cell function was impaired 1-3 hours after eating the protein. If you eat three 50 gram servings of protein a day and immune cell function is only impaired for an hour, that leaves 22 hours where it is “normal”.

Sadly though, for most people it’s likely not normal.

The average person’s lifestyle probably has several other insults that are also not heart healthy. They are not exercising, they are not sleeping well, they are stressed, their diet is poor, they may smoke and/or drink excessively.

Given most people are living a lifestyle that is already not doing their heart health any benefits should we then concierge recommending limiting protein intake?

Again, in my opinion, no.

Protein is likely going to be the least processed food item in most people’s diet and is coming with the most health benefits. If you reduce the protein in the average person’s diet do you think they will replace it with fruits and vegetables?

Likely not, they are going to replace it with more processed food.

Will that result in better heart health?

Also no, because the rest of their lifestyle is still not doing their heart health any benefits so we will therefore not see an improvement in cardiovascular disease risk.

Protein comes with far too many benefits both in healthy individuals but especially those who are living a standard western lifestyle. It provides micronutrients, keeps you fuller for longer, provides the building blocks to help maintain and build muscle and allows you to live independently well into old age. To remove it to improve heart health when the average individual is not going to change anything else about their lifestyle to improve their (heart) health will only make things worse in my opinion not better.

Even if you are healthy, the small downregulation of immune cell function for a couple hours after you eat is likely not going to have a negative impact in the long term.

If you care about your heart health focus on the things we know you can do that really move the needle, exercise regularly, get adequate sleep, moderate your stress, eat a whole foods diet including protein, pay attention to your lipids, make sure you are not constantly inflamed…basically do all the lifestyle practices that we know promote good overall health. All of this is what I promote via my newsletter. So if you are looking to improve your cardiovascular and overall health sign up for my newsletter using the form below and move your health in a more positive direction.

References

Identification of a leucine-mediated threshold effect governing macrophage mTOR signalling and cardiovascular risk. (2024, February 19). PubMed. Retrieved March 4, 2024, from https://pubmed.ncbi.nlm.nih.gov/38409323/