I love when things pop up that are near and dear to my heart...
First, if you suspect low testosterone levels, see your doctor. It's a real quick easy blood test to check, and clinical low testosterone is
very easily treated. Symptoms include chronic fatigue, loss of strength, depression, fat accumulation especially around the waist, and low libido. If you are actually
deficient, your doctor will either give you regular injections or a script for Androgel or Testim - a Purell-like goop containing testosterone that absorbs through the skin.
If you're just looking to maximize natural production, you do have some avenues available.
1. SLEEP
Insufficient sleep screws up your body's hormones in more ways than I care to think about. Insulin, GH, testosterone, adrenaline, cortisol... everything goes bonkers when you're sleep deprived.
2. DIET
EAT FOOD. You probably know this one already, you need to get the bulk of your nutrition from whole foods, or the body doesn't process them correctly and metabolic process start shutting down. Also worth mentioning, cholesterol is the mother of all hormones. Your body can't produce any of them without it. If you're eating a very low fat diet, stop that at once. Get your good fats, get your cholesterol.
3. WORK OUT
Physical activity can - and does - raise testosterone. In men, this hormone plays a huge role in muscle development, and your body will release it in response to the stresses you subject it to in order to successfully build muscle.
4. LIMIT PHYTOESTROGENS
Have I given my anti-soy tirade lately? If not, let me go ahead and do so now. Phytoestrogens are essentially compounds that aren't really estrogen, but they produce the same physiological response. BPA gets a lot of press on this one - so if you have an ancient water bottle, think about ditching it for a BPA-free one. Also avoid acidic canned goods, like tomatoes. Generally, cans are not a big issue, but acidic foods will eat the BPA off the liner and it ends up in the food. The king of phytoestrogen, however, and no one seems to want to talk about this, is processed soy.
Human beings are not designed to consume processed soy. Generally, one or two servings is no big deal, but eating it in any large quantity is unwise. Male or female, excess exogenous estrogen is
bad. Terribad. Like cancer-causing bad, nevermind low testosterone (and yes, it does that, too). If you are consuming lots of processed soy, knock it off. If you don't know if you're consuming lots of processed soy, start reading labels, and actively eliminate it the same way you would eradicate HFCS. Yes, I know there are studies that say the soy-phytoestrogen study is overblown, but I have seen exactly zero of such studies that
weren't funded by companies and organizations that have a vested interest in selling soy products. It's a phytoestrogen. We know what phytoestrogens do in the body. Therefore, we know that regardless of what soy peddlers tell us, we should probably not be eating it by the truckload. When I see unbiased empirical research proving otherwise, I'll believe it.
5. GET LAID
Seriously. About once a week. This is a well-studied and little-known piece of information that testosterone levels plummet if a guy doesn't "release" for over a week.
6. SUPPLEMENT WITH ZMA
Yes, Zinc alone works, but Magnesium and B6 aid with absorption, and ZMA (zinc monomethionine aspartate) is more bioavailable than plain old zinc. This is clinically proven to increase testosterone in athletes, as well as help you sleep better. It's best taken on an empty stomach close to bed time. You want asparate forms, not chelated forms. A good supplement should contain 11 mg of Vitamin B-6, 30 mg of the zinc monomethionine aspartate, and 450 mg of the magnesium aspartate per serving. Do not take it with calcium, and do not buy one that contains calcium, as calcium will block absorption. (@lv2snwbrd if you want studies, I can probably dig some up for you, it'll just take me a little time cuz I'm retarded busy lately

)
7. AVOID BOOZE
Booze lowers testosterone production, and in excess, increases estrogen production. A beer or two? No big deal. One night with a serious buzz? Whatever. Regular intoxication? Bad idea.
Theres a litany of other things to avoid, because they simply don't work. Tribulus terrestris is a great supplement - for manufacturer's wallets, and nothing else. It's been proven worthless in several studies (and
Mark has slammed it too). DHEA also falls under doesn't really work. 50mg a day can be marginally helpful, but beyond that your body will actually convert it into estradiol, not testosterone (and enough estradiol means you, too, can experience the joys of PMS).
Last but not least, you can always
get Mark's opinion on the matter.TL;DR - Sleep, diet, don't drink to excess, get your fats, take ZMA on an empty stomach at bed time, and don't buy garbage products that make incredulous claims. The same basic advice we give for most everything. Oh, and have more sex (which I'm sure you'll just resent having to do so much...

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