Is your tendon health negatively impacted by high cholesterol? I originally asked myself this question as a constantly-injured ultra runner with several increasingly problematic Achilles tendon issues. I also tend to have high cholesterol and triglycerides, which I’m dealing with primarily through diet and weight loss. I’d read online that high cholesterol might be bad for tendons–and wondered if this might be part of my problem–but is that true?
Origin of Possible Link
As far as I can tell, the popular impression of a link between high cholesterol (HC, aka hypercholesterolemia) and jacked up tendons (tendinosis or more generally tendinopathy) comes from a 2015 BJSM article. The authors’ meta-analysis of several databases found a link between tendon thickening and pain and high cholesterol, which they summarized as follows:
Meta-analysis of appropriate studies showed significantly higher total cholesterol, low-density lipoprotein cholesterol and triglyceride, and lower high-density lipoprotein cholesterol in individuals with tendon pain/abnormality. Two of the three studies that examined the correlation between tendon thickness and lipid levels found a significant positive relationship. Statin use was associated with Achilles tendon rupture in women but not men.
In other words, they did find a positive link between high cholesterol and tendon issues, but were not able to show causality (did one cause the other) or direction (did poor tendons result from high cholesterol, or did people with high cholesterol have habits or issues such as obesity that might otherwise explain tendon issues). Dozens of articles and blogs then referenced this study and guessed about possible reasons for the relationship.
Is There a Real Link?
Maybe. There have been some follow ups to the 2015 study (see below), but most are focused on animals rather than humans. So it seems that the best you can say is that high cholesterol (HC) and tendinopathy are probably related, somehow, but it’s not clear a) if the relationship is causal (b) how high your cholesterol would need to be to cause damage (c) how low your cholesterol would need to be to reduce damage or encourage healing or (d) if this meta-study would even hold up under a more recent confirmation or analysis…which seems to be lacking.
It’s good to keep your cholesterol down anyway, though, ironically, Statin drugs are also linked to tendon damage, but it’s not clear that this will help your tendons (or failing to do so will hurt them).
Tendinopathy & Cholesterol Resources
“Association of Achilles tendon thickness and LDL-cholesterol levels in patients with hypercholesterolemia,” in Lipids in Health and Disease (2018), which found a thick tendons diagnostically useful in predicting high cholesterol, but was otherwise unhelpful in relating HC to tendon damage.
“Exploring the role of hypercholesterolemia in tendon health and repair,” in the Muscle, Ligaments and Tendons Journal (2014), which is largely focused on rat and mouse studies.
“The impact of cholesterol deposits on the fibrillar architecture of the Achilles tendon in a rabbit model of hypercholesterolemia” in the Journal of Orthopaedic Surgery and Research (2019), which focused on rabbit tendons:
Our findings support the hypothesis that hypercholesterolemia coincides with the weakening of the tendons. It is likely that the intimate contact between collagen fibrils and cholesterol deposits contributes to the weakening of the fibrillar structure of the tendons.
“Is higher serum cholesterol associated with altered tendon structure or tendon pain? A systematic review” in the British Journal of Sports Medicine (2015), which found a positive relationship between tendons and HC, but no causality or direction:
Objective: To determine whether lipid levels are associated with abnormal tendon structure or the presence of tendon pain. Methods: We conducted a systematic review and meta-analysis. Relevant articles were found through an electronic search of 6 medical databases—MEDLINE, Cochrane, AMED, EMBASE, Web of Science and Scopus. Results :17 studies (2612 participants) were eligible for inclusion in the review. People with altered tendon structure or tendon pain had significantly higher total cholesterol, low-density lipoprotein cholesterol and triglycerides, as well as lower high-density lipoprotein cholesterol; with mean difference values of 0.66, 1.00, 0.33, and −0.19 mmol/L, respectively.
“Tendinopathy” on Wikipedia.
Better Resources or Information?
Just let me know. This is not a scientific or even rigorous analysis; just an attempt to find the signal in the noise and keep my own notes.
Image Attribution: Running Bug. Thank you!