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Low Testosterone
•Last Updated: August 14, 2023
Low testosterone results from a problem in the testicles or the brain and can cause low libido, muscle loss, and/or depressed mood. It is primarily treated with testosterone replacement therapy.
Low Testosterone falls under theMen’s Healthcategory.
Last Updated:August 14, 2023
Low testosterone, or hypogonadism, occurs when the testicles fail to produce normal levels of testosterone due to issues within the hypothalamic-pituitary-testicular axis. Testosterone is the primary male sex hormone that is responsible for developing and maintaining secondary male characteristics.
The main signs and symptoms of low testosterone include low sex drive, erectile dysfunction, reduced muscle mass, increased fat mass, low bone density, loss of body hair, gynaecomastia, sleep disturbances, and reduced energy accompanied by depressed mood and trouble concentrating. These symptoms can significantly affect overall health and well-being.
Low testosterone is diagnosed through blood tests that measure testosterone levels; the tests are typically conducted in the morning while fasting. A diagnosis requires 2 separate low testosterone measurements, along with clinical signs and symptoms; low testosterone is defined as a total level that is less than 231 to 275 ng/dL.
Testosterone replacement therapy (TRT) is the primary treatment for low testosterone, and it is available in various forms such as injections, gels, and patches. Although it is generally considered safe, TRT can have side effects and is contraindicated for people with certain medical conditions.
Although many supplements are marketed as testosterone boosters, there is limited evidence to support their effectiveness in raising testosterone levels. However, certain nutrients like vitamin D, zinc, and magnesium may slightly increase testosterone if dietary intakes are insufficient.
Diet can significantly affect testosterone levels because a hypocaloric diet may boost testosterone in men with excess body fat or chronic diseases and potentially lower levels in lean men. Additionally, low-fat diets (≤25% of energy intake) may decrease testosterone compared to higher-fat diets (approximately 40% of energy intake).
Exercise — including aerobic, high-intensity interval, and resistance training — can boost testosterone levels, particularly when it is combined with weight loss efforts, and it may enhance the effectiveness of testosterone replacement therapy. Additionally, bariatric surgery is an effective treatment for increasing testosterone levels in men with obesity.
Low testosterone can be caused by primary hypogonadism, which originates from issues in the testicles, or secondary hypogonadism, which stems from problems in the hypothalamus or pituitary gland. Additionally, it can be classified as functional hypogonadism, which is caused by reversible factors like obesity and aging, or organic hypogonadism, which results from largely irreversible conditions.
Research FeedRead all studies
To naturally increase testosterone, prioritize quality sleep, physical activity, and weight management. Although some supplements may help maintain healthy testosterone levels, many that are marketed as testosterone boosters are ineffective, although they might enhance libido.
Testosterone is an androgen, a male sex hormone, though women need it too. In men, low testosterone has been associated with low libido[59] and poor health outcomes, such as the development of metabolic syndrome.[60] In men and women, low testosterone has been associated with depression.[61][62]
Middle-aged[25] and older[26] men see their testosterone levels decrease by 0.4% to 1.6% per year, and many are the men who experience lower-than-average levels even in their 30s.[27] Fortunately, quality sleep, physical activity, weight management, magnesium, zinc, and vitamin D can all help sustain healthy testosterone levels.
Lifestyle
To optimize your testosterone levels, you don’t only need the proper amounts of vitamins and minerals; you also need to sleep well, exercise, and keep a healthy weight.
1. Sleep
Lack of sleep causes numerous health issues. Notably, it decreases testosterone production[63][64][65][66][67] and facilitates fat gain[68] (and we’ll see that fat gain itself can impair testosterone production). Getting enough quality sleep is so important that we will be publishing an article on that soon.
2. Physical activity
Resistance training can raise testosterone levels for 15–30 minutes post-exercise.[16][17] More importantly, it can benefit testosterone production in the long run by improving body composition and reducing insulin resistance.[16]
Overtraining, however, is counterproductive. Prolonged endurance exercise especially can cause your testosterone to drop.[18][19] Ensuring adequate recovery time will help you receive the full benefits of physical activity.
3. Weight management
Weight gain and the associated chronic diseases, such as cardiovascular disease and type 2 diabetes,[21][22][23] are strongly linked to decreases in testosterone, particularly in middle-aged and older men.
If you gain weight (as fat), your testosterone production drops. Fortunately, if you lose weight, your testosterone production can climb back up.
Adapted from Grossmann and Matsumoto. J Clin Endocrinol Metab. 2017.[8]
As this figure shows, observational studies have seen consistent results: in people who are overweight or obese, the greater the weight loss, the greater the testosterone increase.[21]
These results have been echoed in clinical trials. A meta-analysis of 24 RCTs looked at weight loss caused by diet or bariatric surgery:[15] In the diet studies, the average 9.8% weight loss was linked to a testosterone increase of 2.9 nmol/L (84 ng/dL). In the bariatric-surgery studies, the average 32% weight loss was linked to a testosterone increase of 8.7 nmol/L (251 ng/dL).
You need not lose huge amounts of weight to see a bump in testosterone levels, either: a 5% loss in weight can increase total testosterone by 2 nmol/L (58 ng/dL).[24]
Quality sleep, physical activity, and weight management support healthy testosterone levels, and they’re synergistic: If you lack sleep, you find it harder to exercise and easier to gain fat. If you exercise, you find it easier to sleep and to keep a healthy weight. If your weight is healthy, you find it easier to exercise and easier to sleep.
If you want to know more about the lifestyle-testosterone connection, check out our infographic and article here.
Supplements
Only a few supplements have been shown to benefit testosterone production. Among those, the evidence mostly supports vitamin D and zinc, followed by magnesium. Two caveats should be kept in mind, however:
-
Supplementing with a vitamin or mineral is likely to help you only if you suffer from a deficiency or an insufficiency in this vitamin or mineral.
-
Correcting a deficiency or an insufficiency is more likely to raise your testosterone levels if they are low.
1. Vitamin D
Vitamin D helps regulate testosterone levels.[69][70] Ideally, you would produce all the vitamin D you need through sunlight exposure, but if you live far from the equator, have dark skin, or simply spend most of your time inside, you may need to complement your own production with the help of foods or supplements.
Serum 25(OH)D concentrations
In Canada and the United States, the Recommended Daily Allowance (RDA) for vitamin D falls between 400 and 800 IU (International Units).[71] These amounts, which have been criticized as too low by some,[72][73] are attainable from only a few food sources, which is why vitamin D has become a popular supplement.
| AGE | MALE | FEMALE | PREGNANT | LACTATING |
|---|---|---|---|---|
| 0–12 months | 400** | 400** | — | — |
| 1–13 years | 600 | 600 | — | — |
| 14–18 years | 600 | 600 | 600 | 600 |
| 19–50 years | 600 | 600 | 600 | 600 |
| 51–70 years | 600 | 600 | — | — |
| >70 years | 800 | 800 | — | — |
* 40 IU = 1 mcg | ** Adequate intake (AI)
Reference: Institute of Medicine. Dietary Reference Intakes for Adequacy: Calcium and Vitamin D (chapter 5 in Dietary Reference Intakes for Calcium and Vitamin D. The National Academies Press. 2011. DOI:10.17226/13050)
2. Zinc
Zinc deficiency can hinder testosterone production.[74][75] Like magnesium, zinc is lost through sweat,[76] so athletes and other people who sweat a lot are more likely to be deficient. Although dietary zinc is mostly found in animal products, zinc-rich foods include some grains and nuts.
| AGE | MALE | FEMALE | PREGNANT | LACTATING |
|---|---|---|---|---|
| 0–6 months | 2* | 2* | — | — |
| 7–12 months | 3 | 3 | — | — |
| 1–3 years | 3 | 3 | — | — |
| 4–8 years | 5 | 5 | — | — |
| 9–13 years | 8 | 8 | — | — |
| 14–18 years | 11 | 9 | 12 | 13 |
| 19+ years | 11 | 8 | 11 | 12 |
* Adequate Intake (AI) Reference: Institute of Medicine. Zinc (chapter 12 in Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. The National Academies Press. 2001. DOI:10.17226/10026)
Consuming much more than your RDA[77] can be harmful. In the short term, high doses can cause nausea[78] and vomiting.[79] In the long term, they can lead to a copper deficiency.[80][81]
3. Magnesium
In males with low magnesium levels and low testosterone levels, an increase in magnesium intake can translate into an increase in testosterone production,[82] both directly and (since one of magnesium’s functions in your body is to help convert vitamin D into its active form[83]) indirectly.
While more common in the older population,[84] magnesium deficiency isn’t unknown in younger people (notably athletes,[85] since, link zinc, magnesium is lost through sweat[76][86][87]). Yet getting your RDA should be easy: magnesium-rich foods are numerous and can fit all kinds of diets.
| AGE | MALE | FEMALE | PREGNANT | LACTATING |
|---|---|---|---|---|
| 0–6 months | 30* | 30* | — | — |
| 7–12 months | 75* | 75* | — | — |
| 1–3 years | 80 | 80 | — | — |
| 4–8 years | 130 | 130 | — | — |
| 9–13 years | 240 | 240 | — | — |
| 14–18 years | 410 | 360 | 400 | 360 |
| 19-30 years | 400 | 310 | 350 | 310 |
| 31–50 years | 420 | 320 | 360 | 320 |
| >51 years | 420 | 320 | — | — |
* Adequate intake (AI)
Reference: Institute of Medicine. Magnesium (chapter 6 in Dietary Reference Intakes for Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride. The National Academies Press. 1997. [88])
If you still feel the need to supplement, keep in mind that supplemental magnesium is more likely than dietary magnesium to cause adverse effects, which is why the FDA fixed at 350 mg the Tolerable Upper Intake Level for magnesium supplementation in adults. Also, you may want to avoid magnesium oxide: it has poor bioavailability (rats absorbed only 15% in one study,[89] and humans only 4% in another[90]) and can cause intestinal discomfort and diarrhea.
Overhyped supplements
Numerous products are advertised as testosterone boosters, but the vast majority don’t work, though some can make you believe they do by boosting your libido. Maca, for instance, can enhance libido without affecting testosterone.[91][92][93][94]
Maybe the most popular “testosterone booster” is D-aspartic acid (DAA, or D-aspartate). DAA did increase testosterone levels in two studies, one that used 2.66 g/day[95] and the other 3.12 g/day,[96] but two later studies found no increase with 3 g/day,[97][98] and the latest even noted a decrease with 6 g/day.[97]
Eat a healthy, balanced diet, so as to avoid nutritional deficiencies. If your testosterone levels are low, pay attention to your intakes of vitamin D, zinc, and magnesium. Be skeptical of supplements marketed as testosterone boosters; there’s a good chance the only thing these supplements will boost is their manufacturers’ bottom lines.
Bottom line
The interventions discussed in this article will work best for men with low testosterone, but they can also help men with normal testosterone to sustain their levels, year after year.
Supplements can help, but they can’t replace a healthy lifestyle. In order to optimize your testosterone production, make sure you get enough quality sleep on a daily basis, incorporate some resistance training into your workout program, and monitor your weight.
Try to get enough vitamin D, zinc, and magnesium through your diet. However, if dietary changes prove insufficient, supplementation can help make up the difference.
Not all testosterone deficiencies can be fixed through lifestyle or supplement interventions. It may be prudent to speak with your doctor if the options discussed above do not yield sufficient results.
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