What Affects Cholesterol More: Diet or Exercise?

If you’re worried about high cholesterol, you may be wondering, “How can I lower my cholesterol level? Where do I even begin?”

Not to worry! While high cholesterol can be scary, lowering your cholesterol can also be relatively straightforward. The secret is diet and exercise. While simple, in theory, implementing a diet and exercise regimen can be challenging at first, but over time it gets easier.

Let’s take a look at how you can reduce your cholesterol today and what changes have the most impact on your cholesterol level.

What Is Cholesterol and How Does it Affect Health?

Cholesterol is an essential substance in the body. Despite its importance, there is a misconception that cholesterol is all bad. In fact, cholesterol is mostly good but becomes a problem when there is too much. So-called good and bad cholesterol also play a role.

However, the idea of “good” and “bad” cholesterol is a bit misleading. Cholesterol is a necessary substance and is involved in many functions throughout the body. It helps animals, including humans, synthesize hormones.¹

Though it mostly serves a positive role in the body, high levels of cholesterol can be harmful. Cholesterol levels have often been used as a surrogate for measures of overall health, particularly heart health. Indeed, high cholesterol can increase your risk of heart attack and stroke. That has more to do with carrier proteins, which we’ll discuss briefly.

 

What’s the Deal With Good and Bad Cholesterol and Carrier Proteins?

There are at least two primary carrier proteins for cholesterol, HDL and LDL. HDL is often called “good” cholesterol, while LDL is referred to as “bad” cholesterol. Both are necessary to transport cholesterol throughout the body. Both “forms” of cholesterol are acceptable in small quantities.

But things get messy when we have too much cholesterol. Our bodies produce excess LDL, and it stops transporting cholesterol. This excess LDL can contribute to the formation of plaques,² increasing your risk for heart attack and stroke.³

All of this is to say: high cholesterol levels can be dangerous, but it’s through an indirect reaction.

 

How Does Diet Affect Cholesterol?

Some foods contain high levels of cholesterol. Red meat is the biggest offender, but other meats and fish also contain cholesterol. It stands to reason that reducing your intake of meat, especially red meat, can and will reduce your cholesterol considerably.⁴

While this is true, it’s a bit of an oversimplification. See, our bodies naturally produce cholesterol. So, while dietary cholesterol can increase the blood’s cholesterol level, it’s not the only factor. Let’s talk about exercise briefly before evaluating the overall impact of lifestyle choices on cholesterol.

 

How Does Exercise Affect Cholesterol?

Exercise can also help to reduce cholesterol, but maybe not in the way you think. Think about it: exercising burns calories, not cholesterol. The two ways cholesterol accumulates in the body is through diet and natural synthesis. So, how does exercise even affect cholesterol at all?

Researchers have found that more important than diet or exercise (when considered in isolation) is overall health. They found a very high relationship between weight (BMI, specifically) and cholesterol levels.⁵ Healthy individuals with lower BMI consistently had lower cholesterol levels than those with a higher BMI. This was true, regardless of diet or other lifestyle choices.

 

Wait, So What Does This Mean? Which Is More Important?

This may be a bit confusing at this point. Diet and exercise are important for lowering cholesterol, but the evidence shows that they work best together.

Sure, you can cut out red meat from your diet to help lower your cholesterol but, if you’re overweight, looking to eat a well-rounded diet and introducing more physical activity into your daily routine may be a better long-term lifestyle goal than simply reducing dietary cholesterol.

Losing weight can be difficult and requires both diet and exercise. This doesn’t have to be anything drastic. Think about the example earlier: If you eliminate red meat, that will help reduce your cholesterol. However, if you simply improve your diet and start exercising, you might not need to eliminate red meat.

In other words: Find a diet that works for you and helps you maintain a healthy weight. That’s the most important choice!

If you simply must know which is more important, think about this: If your weight is not a concern, then the answer is obvious: diet. Where else would you acquire excess cholesterol?

 

Making Healthy Choices

As with most things, making healthy choices every day is the single most important thing you can do for your body. You don’t have to go on a restrictive diet if that doesn’t feel right for you. Instead, just think about making better choices overall.

Eat more whole foods. Cook instead of going out. Exercise several times a week. Each little thing adds up. Over time, you won’t just lower your cholesterol. You’ll improve your health in many other ways, too!

References

1. Hanukoglu I. Steroidogenic enzymes: Structure, function, and role in regulation of steroid hormone biosynthesis. J Steroid Biochem Mol Biol. 1992;43(8):779-804. DOI: 10.1016/0960-0760(92)90307-5.
2. Stocker R., Keaney Jr. J. F. Role of Oxidative Modifications in Atherosclerosis. Physiol Rev. 2004;84(4):1381-1478. DOI: 10.1152/physrev.00047.2003.
3. National Heart, Lung, and Blood Institute. Third Report of the National Cholesterol Education Program (NCEP) expert panel on detection, evaluation, and treatment of high blood cholesterol in adults (Adult Treatment Panel III) executive summary. National Institutes of Health. 2001.
4. Key Elements of Healthy Eating Patterns. Chapter 1 in 2015-2020 Dietary Guidelines. https://health.gov/our-work/food-nutrition/2015-2020-dietary-guidelines/guidelines/chapter-1/a-closer-look-inside-healthy-eating-patterns. Accessed 10/5/2020.
5. Santos F.L., Esteves S.S., da Costa Pereira A., Yancy Jr. W. S., Nunes, J.P.L. Systematic review and meta‐analysis of clinical trials of the effects of low carbohydrate diets on cardiovascular risk factors. Obes Rev. 2012;13(11):1048-1066. DOI: 10.1111/j.1467-789X.2012.01021.x.