Heart Health in Thyroid Disease

When I check the box for lipids on lab work, I often get a questioning look from patients. “Why are you checking my cholesterol on a thyroid panel?” At first glance it may seem unrelated but in reality, it can be very important!

So, why do I check lipid levels often in thyroid patients?

Your thyroid not only impacts metabolism, weight, bone health, mood, digestive function, and your menstrual cycle, but also your lipid levels – like cholesterol.

Clinically, I have seen correlations to increased lipids levels on lab work when a patient’s thyroid function is suboptimal. Why is this?

Your thyroid gland plays an important role in regulating cholesterol. When you are hypothyroid (your thyroid isn’t working well enough) your lipid levels, including cholesterol, often elevate. This is because your body is not removing lipids as well as it should and bad cholesterol starts to accumulate.

Now, it is important to note that cholesterol in our blood stream is present in two basic forms: high-density lipoprotein (HDL) and low-density lipoprotein (LDL). HDL is “good cholesterol”, it helps to reduce the amount of cholesterol in the body. LDL is “bad cholesterol” and is what will start to build up if thyroid levels are not well controlled. This is what is known to clog your arteries.

How sluggish does my thyroid have to be for the changes to occur?

For many people, even a little dip in thyroid levels can cause major impacts on your lipids. You don’t have to be way out of the normal range! And it’s not just the Thyroid hormones you have to watch but also TSH. If your TSH is elevated but your thyroid hormones are normal, your cholesterol could elevate.

Now why is this important?

Well, we have all heard that cholesterol is dangerous at high levels and this is very true. Elevated cholesterol can lead to cardiovascular disease. If cholesterol is not broken down properly/ it can start to form plaques in arteries and lead to obstruction of these arteries. Now most information out there about cholesterol is related to lifestyle, which is also very important, but just one piece of the puzzle in thyroid disease. Yes, you may need to take a good look at what you are eating but for many of my patients this is not always the case. They have outstanding diets, exercise regularly but come to see me with elevated cholesterol levels. If these patients are also experiencing hypothyroid symptoms this may be an important factor to consider. All in all, if you have high cholesterol, you should be screened for hypothyroidism.

References:

• Ross DS. Lipid abnormalities in thyroid disease. https://www.uptodate.com/contents/lipid-abnormalities-in-thyroid-disease?search=thyroid%20cholesterol&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1. Accessed April 13, 2020.