Androgenic-anabolic steroids (AAS) have been used to enhance athletic performance since the 1940s, but some of the health risks of steroid abuse have only recently come to light. Anabolic steroids have widespread effects on the body and its internal systems, so it’s not surprising that aside from their potential effect on muscle growth, they can harm other cells and organs. That's why regular health screening and blood testing is so important.

How do anabolic steroids work?

Anabolic steroids are synthetic derivatives of the hormone testosterone which amongst other things is responsible for muscle development - “the anabolic effect”, and the development of male sexual characteristics - “the androgenic effect”.

Anabolic steroids work in several different ways in the body:

1. When we lift heavy weights we create tiny micro-tears in muscle fibres. Testosterone stimulates the creation of new and bigger muscle fibres in reaction to this. Anabolic steroids tend to cause an exaggerated version of this reaction due to the high doses people use.
2. Anabolic steroids stimulate production of growth hormone (GH) which in turn stimulates the production of IGF-1. IGF-1 has growth-promoting effects on almost every cell in the body especially skeletal muscle, cartilage and bone.
3. Intense exercise releases cortisol known as the stress hormone, which breaks down muscle tissue. Anabolic steroids inhibit this breakdown resulting in an overall anabolic effect.
4. There is evidence that anabolic steroids may increase oxygen uptake and increase cardiac output.
5. Anabolic steroids may also improve athletic performance by increasing aggressive behaviour.

Unintended physical consequences

A common misconception is that because anabolic steroids are a man-made derivative of a hormone occurring naturally in the body they should be safe to supplement with. The human body controls the blood and tissue levels of testosterone within a small range as too high or low a concentration can be harmful. However the typical doses taken as supplements by athletes are significantly higher than the amount that naturally circulates in our system. Use of anabolic steroids can therefore lead to multiple harmful physical side effects with shrunken testicles and male breast growth probably the most well known. An excess of androgens resulting from steroid use can also lead to male-pattern baldness, severe treatment resistant acne as well as altered libido.

Chronic steroid use causes the body to stop its own internal production of testosterone in an effort to maintain a constant level. This can lead to shrunken testicles that can no longer produce testosterone themselves. In addition, testosterone is converted to oestrogens which are important for modulating libido, erectile function and sperm generation. However an excess of testosterone can raise oestrogen to abnormal levels resulting in gynecomastia or the enlargement of male breasts. These effects can be permanent.

What lies beneath

In addition to the more noticeable effects associated with steroid use, there are other potential consequences that may not be so obvious but can pose a serious health risk. While blood testing can help pick up some of the abnormalities associated with excessive anabolic steroid use it is important to be aware that many of the harmful effects may not cause abnormalities in the blood until it is too late. It is also important to be aware that many of the treatments for the conditions described below are less likely to work with continued steroid use.

Here we describe 7 ways that anabolic steroids can damage your health without you even realising it:

1. Cardiovascular disease

There have been many studies on the impacts of anabolic steroids on the cardiovascular system in athletes and bodybuilders. Steroids have been shown to increase levels of LDL (bad cholesterol) and decrease levels of HDL (good cholesterol) - this increases the risk of atherosclerosis (hardening of the arteries) and heart disease such as angina, heart attacks and sudden cardiac death. Similarly steroid use is also associated with elevated C-reactive protein (CRP) levels – CRP is an marker of inflammation within the body and there is evidence that constant high levels may predispose people to cardiovascular disease.

Chronic steroid use can affect heart muscle causing a condition known as left ventricular hypertrophy which is an enlargement and thickening of the walls of the heart's main pumping chamber. The enlarged heart muscle loses elasticity and eventually may fail to pump with as much force as needed. This is known as heart failure and is a common cause of disability and death in the elderly.

High blood pressure has been reported in some cases of anabolic steroid use which further increases the risk of cardiovascular disease.

2. Liver toxicity

Most metabolism of anabolic steroids occurs in the liver which is therefore prone to damage. Whilst athletes with pre-existing liver conditions are most at risk the damage can occur in anyone. The two markers of liver stress most commonly elevated in users of anabolic steroids are the enzymes ALT and AST. These enzymes are necessary for amino acid metabolism in the liver and will leak into the bloodstream as the liver becomes inflamed or damaged. ALP and GGT are also important markers of liver health during steroid use, and elevated levels can indicate liver toxicity. It is important to be aware that significant liver damage can be occurring even with normal liver function tests and that often the blood levels of these liver markers only start rising when the damage is severe enough.

3. Kidney injury

One of the kidneys many crucial functions is acting as a filter for the blood, removing excess waste products in the body. Bodybuilders frequently use dietary supplements including protein, creatine and vitamins to build strength and muscle bulk. High-protein intake is a concern as it increases the demand on the kidneys to filter off the excess products of protein metabolism. Often this is not a huge problem on its own, but when high-protein intake is combined with anabolic steroid use, this compounds the load on the kidneys and can lead to scarring and possibly kidney failure.

4. Infertility

Chronic anabolic steroid use causes a decrease in luteinising hormone (LH), and follicle-stimulating hormone (FSH) which are needed for sperm generation. This can cause a decrease in sperm count and mobility. Decreases in LH and FSH can be seen within 24 hours of beginning anabolic steroid use, and infertility may result within months. Usually infertility is reversible typically within 1 year of stopping steroid use, but it can take longer particularly in long-term users.

Men may also experience priapism, impotence, difficulty or pain with urination, and a possible increased risk for prostate cancer, which is why a regular prostate check is important.

5. Impaired glucose tolerance

Studies have shown that anabolic steroid use affects the body’s ability to handle sugar and can lead to type 2 diabetes. This can have a devastating health impact and further increase the risk of kidney damage, heart disease, strokes and blindness amongst other things. Testing of fasting blood sugar can help pick this up early before these complications start to arise.

6. Blood disorders

Anabolic steroid use increases stimulates the production of red blood cells and also increases the levels of haemoglobin (the protein in red blood cells that carries oxygen) and haematocrit (the percentage of red blood cells in the blood). This can result in a condition known as testosterone–induced polycythaemia or “sludging”. This causes the blood to become thicker which can in some people trigger life threatening blood clots to form in the bloodstream.

7. Thyroid dysfunction

Studies have shown negative effects of anabolic steroids on thyroid function. The thyroid is responsible for a huge number of important metabolic processes, and a thyroid hormone imbalance can cause a wide range of health issues (refer to our blog on thyroid function for more information). An annual thyroid check is important to keep track of thyroid function. Find out more with our Thyroid Check.

The importance of blood work

The use of anabolic steroids can lead to a number of negative health consequences most notably with cardiovascular and liver health. By the time physical symptoms of these develop, permanent harm may already have been done. The safest medical advice that any health professional would give you is to stop using these due to their risks. However, if you chose to continue taking these supplements it is important to be vigilant for any signs you may be harming your health. As discussed in this blog some of these effects can be identified in blood work before physical symptoms become apparent. These are the blood tests we recommend:

• Cholesterol status - there are many factors which contribute to your cardiovascular health. Your cholesterol (both high density and low density lipoproteins) and triglyceride levels are one risk factor we can assess by blood testing.
• Inflammation – the biomarkers c-reactive protein and creatine kinase provide insight into cardiovascular disease and muscle damage.
• Liver function test - your liver processes drugs and filters toxic chemicals. Liver damage is often evident from the assessment of liver enzymes and other key markers of liver function.
• Kidney function test - your kidneys filter waste from your body. Extreme athletes are more at risk of kidney failure due to high protein intake, excessive muscle breakdown from intense exercise as well as anabolic steroid use. Measuring key waste products as well as electrolytes, minerals and glucose provides good insight into kidney function.
• Full blood count – measuring steroid-induced increases in red blood cell count, haematocrit, and haemoglobin concentrations are important in determining the risk of heart attack or stroke.
• Hormone profile – supplementing with anabolic steroids can cause changes in hormone profile over time. Key hormones to measure include the androgens testosterone and free testosterone, as well as FSH, LH and oestradiol.

It is important to understand what your own 'normal' levels are for your blood biomarkers, and to track changes to these over time. Monitoring changes in your health data typically provides greater insight than a single isolated result, and will allow you to track any improvements or declines in performance.

If you want to reduce your health risks, then don’t take anabolic steroids. But if you are supplementing then understand more about how blood testing and health screening can help manage your risk.