Is your weekly cheat day damaging your blood vessels?

I’m a big proponent of low-carb diets such as Paleo and Keto.

After all, these diets have been shown to have multiple health benefits from boosting weight loss to reducing metabolic syndrome and the risk of diabetes and heart disease that comes with it.

Basically, they work by keeping your blood sugar steady, preventing it from going too high, reducing your body’s insulin resistance and stopping those between-meal cravings that can cause you to pack on the pounds.

By removing carbs, they starve the body of its preferred fuel — glucose — and force it to burn fat instead.

But, for many people, their low-carb diet is only a six day a week phenomenon.

They stick to the diet six out of seven days and have one cheat day, where they can eat whatever they want.

Supposedly, this cheat day keeps their body from “adapting” to the diet and prevents weight loss plateaus.

I know, because I’m one of the people that thought a cheat day was beneficial. But now, a new study is calling the theory into question and demonstrating how this six days on, seventh day off philosophy could actually be harming your health.

Your blood vessels after a sugar hit

Since problems with glucose tolerance and spikes in blood sugar are known to be associated with an increased risk of heart disease, researchers at the University of British Columbia, Okanagan decided to look at the effects of a cheat day on blood glucose and blood vessel health.

For their test, the researchers recruited healthy young males and had them consume a 75-gram glucose drink before and after a seven-day high-fat, low-carb diet similar to the keto diet.

This 75-gram sugar hit is about what you would get if you drank a large bottle of soda or ate a plate of fries — pretty common cheat day choices.

While the researchers expected to see things like increased inflammation levels or a reduced tolerance to blood glucose, what they found was actually quite different and much worse…

After sticking to a low-carb diet for a week, a single spike in blood sugar resulted in biomarkers in the blood that suggested that blood vessel walls were being damaged.

Basically, even though the subjects were young and otherwise healthy, after consuming the glucose drink, the results looked like they might have come from someone with poor heart health.

According to the researchers, this happens because when your body responds to an excess of blood sugar, it causes blood vessels cells to shed and possibly die off.

“My concern is that many of the people going on a keto diet — whether it’s to lose weight, to treat Type 2 diabetes, or some other health reason — may be undoing some of the positive impacts on their blood vessels if they suddenly blast them with glucose, especially if these people are at a higher risk for cardiovascular disease in the first place ” said Cody Durrer, UBC Okanagan doctoral student and the study’s first author. “Our data suggest a ketogenic diet is not something you do for six days a week and take Saturday off.”

Protecting your blood vessel health

So, if you are using a low-carb diet to lose weight, improve your blood sugar or just feel better, you might want to think twice before embracing the cheat day theory. With the results of this study, it looks like in order to protect your blood vessel health, sticking to a low-carb diet should be a 24/7 ritual.

In addition to skipping cheat day, you can also boost the health of your blood vessel by taking resveratrol. It’s the polyphenol that comes from the skin of grapes used to make wine and according to the Mayo Clinic, it can not only help prevent damage to blood vessels, but it may also even help lower bad cholesterol and inflammation and prevent blood clots.

It comes down to this — low-carb diets are great for weight loss and preventing metabolic syndrome, but to keep your blood vessels healthy, you need to ditch the cheat day and take resveratrol daily.

Sources:

1. Ketogenic diet: Is the ultimate low-carb diet good for you? — Harvard Health Blog – Harvard Health Publishing
2. Ten Scientifically Proven Benefits of Low-Carb Diets — Doc’s Opinion
3. How Does Low-Carb Work? — Diabetes.co.uk
4. On the keto diet? Ditch the cheat day — University of British Columbia Okanagan campus
5. Red wine and resveratrol: Good for your heart? — Mayo Clinic