Testosterone is an essential hormone for males since their puberty. It is what gives secondary characteristics to a man and provides them with an active sex drive. It is also vital for muscle building and to maintain their bone mass intact.
This hormone is produced by Leydig cells and reaches all of the body through the blood. It is received in almost every tissue through specialized receptors, each one with different functions. In many cells, testosterone contributes to cell growth.
In others, it stimulates protein formation and modulates DNA expression. The effects vary significantly from one cell to the other. That’s why we sometimes get surprised after learning about a new function of testosterone. It is not always about sexual development and muscle building.
In the field of cardiovascular health, sexual hormones protect young women for many years. When they stop synthesizing these hormones, the artery wall and their cholesterol levels change. That’s why many researchers have tried to find similar associations with testosterone. Some of them describe an increase in cardiovascular risk in men with low testosterone. They have a higher risk of heart disease and stroke, for example. Others mention that it is due to a change in cholesterol levels.
In this article, we’re reviewing the evidence that links testosterone with cholesterol, both LDL and HDL. We’re telling you what to expect of testosterone therapy if you have low testosterone levels and what else to do if you want to control bad cholesterol.
Why testosterone therapy?
Why would you receive testosterone therapy? The obvious answer is because you have low testosterone levels, but it is a bit more complicated than that. Not all men with low testosterone levels are prescribed testosterone replacement therapy. You need to meet a few requisites.
Besides your serum levels of testosterone, your doctor may become interested in other values. One of them is known as SHBG. The full name is Sex hormone-binding Globulin (SHBG), and it is a protein in the blood. This protein binds to testosterone, acting as a carrier. But when testosterone is attached to this protein, it is inactive. So, instead of low testosterone levels, you could have high SHBG levels. In that case, you won’t likely benefit much from exogenous testosterone. Other options are available for these cases.
In contrast, testosterone therapy patients can be divided into two main types. The first type is hypogonadism. This term describes a man who has dysfunction in the testis, also known as male gonads. Hypogonadal men do not have enough testosterone. Some of them do not experience puberty changes, either. This is often due to congenital disease or a very severe problem in the testis.
For example, after chemotherapy, radiotherapy, or surgery. In either case, we have an underlying illness that affects the testis, and they do not produce enough testosterone. Replacement therapy is then prescribed to prevent the consequences of low testosterone.
The second group of testosterone treatment patients is senior men. They experience a natural decline of sex hormones, which is expected after aging. However, this decline is sometimes excessive, and they end up with deficient levels. Serum testosterone has a threshold of 300 ng/dL. Even if you’re a senior, your levels should not go below this mark. If they do, you probably need testosterone supplementation.
Every case should be considered separately and according to a man’s age. At 21 years old, your testosterone can reach up to 1080 ng/dl, and this measure is quite variable. So, if you have low testosterone symptoms, talk to your doctor about your concerns. You may need a blood test to rule out low testosterone as the cause of your symptoms. Testosterone replacement therapy will be administered only after diagnosing the problem (1,2).
We can talk about the third group of males who use testosterone. They are men who believe that their testosterone levels are low or use anabolic products for aesthetic purposes. However, this is not a clinical application and is not approved by the FDA. Instead of having additional benefits, this creates an excess that is not well received by the organism. Thus, they often need to take several medications with their own side effects to control the long-term consequences.
Leaving aside this incorrect and often banned use of anabolic hormones, let’s talk about how medical administration and naturally synthesized testosterone can influence cholesterol levels.
Cholesterol and testosterone
Cholesterol is an essential fatty substance we have throughout the body. Contrary to what many people think, cholesterol is not the enemy by itself. It is required in many body functions and cell processes.
For example, it is needed to create testosterone and other hormones. It is also essential to produce new cells after cell division. However, having too much cholesterol in the blood causes cardiovascular disease. It builds up in the artery wall and causes an obstruction known as atherosclerosis.
Atherosclerotic plaques are bulging areas that narrow the artery lumen and compromise blood flow. In the heart, coronary arteries are very small, and further narrowing of these arteries can result in a heart attack. This is also known as coronary artery disease. The problem gets worse if the plaque ruptures due to the blood pressure passing through. A clot is formed all around the area and creates a complete block of the artery (3).
Our society and culture favor high cholesterol levels to an alarming degree. That’s why it is always useful to find ways to reduce cholesterol levels in the blood. However, there are different types of containers of fatty acids in the blood. We can narrow them down to two classes, usually called good cholesterol and bad cholesterol. They are HDL cholesterol and LDL cholesterol, respectively.
LDL (low-density lipoprotein cholesterol) is a donor. It spreads cholesterol throughout the tissues. HDL (high-density lipoprotein cholesterol) is a collector. It cleans the arteries from excess. Thus, it will be ideal for reducing our circulating LDL while increasing our HDL cholesterol.
The link between testosterone and bad cholesterol
When testosterone levels are deficient, it is not rare to find an increase in total cholesterol levels. On the contrary, many patients have described a significant decrease in cholesterol levels after starting testosterone replacement therapy. The link is there, but it is difficult to study because cholesterol metabolism changes according to the diet and other aspects that won’t be easy to control.
Still, different researchers have made efforts to understand the link. Besides cholesterol rises, low testosterone may also lead to high triglyceride levels. These fatty acids are gathered in very-low-density lipoprotein cholesterol or VLDL. So, many VLDL and LDL particles are produced by the liver. At the same time, they circulate for a longer time. Instead of clearing LDL particles from the blood timely, low testosterone slows down the process. The removal of LDL cholesterol is compromised. Thus, it builds up in the blood and causes an increase in total cholesterol (4).
These effects are particularly evident in individuals who have a high-fat diet. So, it is always recommended to modulate your diet according to your cholesterol levels. Your doctor may prescribe cholesterol-lowering medications, but you also need to have a diet. Choosing your fats among healthy sources may also help.
Consuming omega-3 fats has an entirely different effect than eating fried and processed foods. The former cause a steep rise in LDL and bad cholesterol. The latter may even help reducing or to level serum cholesterol levels.
A recent study evaluated these changes when testosterone was around. The investigators found a negative relationship between testosterone and LDL. This means that higher testosterone levels relate to lower LDL levels. The investigators did an excellent job and adjusted their findings to many confounders. For example, thyroid hormones and BMI. After adjusting their results, total cholesterol levels were reduced as well as triglycerides (5).
The evidence so far supports the notion that testosterone reduces our LDL levels. According to these authors’ investigation, a possible explanation has to do with an enzyme known as lipase. This enzyme breaks down fatty acids in the blood. Another explanation would be an improvement in insulin sensitivity triggered by testosterone.
Another study evaluated the effects of starting replacement therapy in cases of low testosterone. The investigators took 22 men with a very low concentration of testosterone. They administered testosterone injections at a dose of 200 mg every second week.
The participants recovered their normal levels of testosterone and had a significant decrease in cholesterol. After 6 months, men with an average 225 mg/dl of total cholesterol ended up with 202 mg/dl. After 1 year, their levels dropped to 198 mg/dl. LDL cholesterol was also reduced from 139 mg/dl to 126 mg/dl after 6 months. After 1 year, their levels dropped to 118 mg/dl. Throughout the clinical trial, no reduction in HDL (good) cholesterol was found (6).
Many questions still remain unanswered, and more research is needed to understand why this happens. However, the prospect is very promising as an alternative for men with low testosterone and high cardiovascular risk.
Testosterone and HDL
As noted above, HDL is a subtype of total cholesterol. We can break it down into bad cholesterol (LDL) and good cholesterol (HDL). The association between testosterone and HDL cholesterol is a bit more complex. It does not remain constant in every study. Thus, different authors have different perspectives about it. There is not a final word, but many promising studies along the way.
For example, in the study reviewed above, there was a significant decrease in LDL and total cholesterol in participants who went through testosterone replacement therapy. As their levels of testosterone returned to normal, so it happened with their blood lipids. However, this reduction of cholesterol did not affect HDL levels. The participants maintained normal HDL levels throughout therapy and after 1 year (5).
Other studies have found the opposite. For example, there was a review published in 2013 reporting a decrease in HDL. The investigators did a comprehensive evaluation of the data published so far. They found authors who reported a reduction of HDL along with LDL cholesterol.
Others mentioned that only LDL cholesterol was reduced. Still, others found no reduction in cholesterol levels. The discrepancy made the authors conclude that it is impossible to give a definitive statement. Given the evidence so far, we don’t really know what to expect of testosterone therapy. At least not in relation to cholesterol levels (6).
Why is there such a discrepancy? It is probably because cholesterol levels depend on many factors. It is not only testosterone. Medications, dietary habits, exercise, and many other variables play a role. Your baseline testosterone could be different from another person. Thus, instead of using testosterone to lower a man’s cholesterol levels, we can use many other methods.
Alternative ways to lower LDL cholesterol
- Avoid processed fats. Remember that these fatty acids are to blame for the most violent rise in LDL cholesterol. Be particularly careful around trans-fat.
- Keep your weight in check. In most cases, a high BMI leads to high LDL cholesterol as well.
- Eat more fiber in your meals. More specifically, you want to look for soluble fiber. This type absorbs bile and takes away cholesterol in bile. It would otherwise be absorbed in the gut, but it is eliminated in your feces instead.
- Use spices in your food. Several spices have an LDL-lowering effect. For example, cinnamon, garlic, black pepper, ginger, coriander, and curcumin.
- Eat a plant-based diet. This type of diet has stanols and sterols. These substances contribute to lowering cardiovascular risk and LDL levels.
Alternative ways to increase HDL cholesterol
- Eat healthy fats: Saturated and trans-fat increase LDL cholesterol. But if you want to raise your good cholesterol, look for sources of healthy fats. Omega 3 fatty acids in fish and nuts are an excellent example.
- Exercise daily: Exercising may reduce your LDL levels. However, one of the most remarkable effects of exercise is raising HDL. You could say that exercise helps your body clean the arteries from excess fats and other toxins.
- Quit smoking: Tobacco smoke has different harmful effects. One of them is reducing your HDL levels. So, if you want to bring them back to your baseline levels, you need to stop smoking. The recovery will be gradual, and you need to keep constant to see a real change.
Conclusion
Testosterone is an important sex hormone in males, with many applications all over the body. Every cell uses testosterone differently, and we still don’t know how it works in specific tissues. However, the effects are clearly visible and measurable.
In women, a reduction of sex hormones (estrogen) causes a sudden rise in cholesterol and cardiovascular risk. In men, sex hormones could have a similar association, but so far, the evidence is not very solid.
For educational purposes, we can narrow down the subtypes of cholesterol particles in two. LDL cholesterol is termed bad cholesterol because it spreads fat throughout the tissues. HDL cholesterol is also known as good cholesterol because it collects fat and cleans the arteries.
What about the association between testosterone and cholesterol?
In many studies, testosterone levels are inversely associated with LDL levels. In other words, males with high testosterone usually have low LDL levels. When they have a testosterone deficiency, the risk of blood lipid problems is higher.
Moreover, introducing testosterone replacement therapy seems to contribute to the solution. These men have a reduction of LDL levels as the therapy stabilizes their testosterone levels.
HDL is a bit more elusive, and many studies found no relationship with testosterone. However, other authors suggest that more testosterone leads to higher levels of HDL.
Testosterone therapy is very complex, and not all patients will receive this type of therapy. High LDL levels are definitely not an indication to start administering testosterone. Instead, the decision is made depending on the patient’s levels and symptoms.
So, if you suspect that you have low testosterone levels, talk to your doctor about your concerns. You may have an additional blood lipids benefit, but remember that this is not the primary purpose of replacement therapy. Other drugs (statins) and many lifestyle recommendations are available to control cholesterol levels more effectively.
