The development of successful sexual behavior involves not only important neuroendocrine and local genital changes that begin at puberty, but also psychological and social influences that occur both before and after puberty.[7,8] Sexual behavior in males is regulated mainly by internal patterns of hormones; i.e. T, progesterone and PRL. These hormones are modulated by the male interactions with the social environment.
a) Some Vegetarians and Vegans. It should be pointed out that certain animal-based foods are known for being the highest providers of niacin. So does this mean that animal-emphasized diets will result in increased blood flow over vegetarians? My experience on the Peak Testosterone Forum has been the opposite and this is the subject of my book The Peak Erectile Strength Diet. Basically, a great many plant foods directly stimulate nitric oxide and will increase blood flow while lowering blood pressure. In fact, some plant foods can lower blood pressure as much as modern hypertension medications. See my page on Flaxseed and Blood Pressure for an example of that. High nitrate foods, such as spinach, arugula and beets, are yet another example.
A conflicting study of 22 subjects found that a 100mg daily dose of yohimbine for 30 days did not significantly improve penile rigidity. Three subjects experienced a notable increase in penile rigidity and twelve subject experience a partial increase in rigidity.  These findings do not completely discount the use of yohimbine to treat erectile dysfunction, but do suggest the compound's effects, even at very high dosages, will cause varying responses across a similar population.
Those looking to crank up their body's fat-burning to the next level may stack yohimbine HCL with ephedrine HCL and caffeine, creating the ECY stack. Yohimbine is a powerful stimulant that acts on different metabolic pathways compared to caffeine and ephedrine. The most common dosage for each compound in this stack is 5mg of yohimbine HCL, 200mg caffeine, and 25mg ephedrine HCL two to three times per day.
The concentration of yohimbine in commercial supplements may vary from one manufacturer to another. A chemical analysis conducted on 26 brands of yohimbe supplement shows that nine products contain no yohimbe extract at all, while eight products contain only small amounts of yohimbine — approximately 0.1 to 1 parts per million (ppm), which is significantly low compared to 7,089 ppm yohimbine in an authentic yohimbe bark.3
You can find this compound as a standalone ingredient in capsule, tablet, or tea form as well as a component of popular pre-workouts and fat burners. Yohimbine is not for everyone - even with moderate dosages it can increase the frequency and severity of panic attacks in high-anxiety individuals, interfere with medications, as well as cause headaches, dizziness, and nausea.
Wistar rats (From Medical Research Institute, Colombo) were obtained and kept in a well ventilated animal house under natural dark light cycle (temperature 28-30°C, humidity; 50-55%). Animals were housed in groups (four per group) until they reached sexual maturity (150-200 g). They were provided with pelleted food and water. Male rats were permitted access to receptive females on three separate occasions and then screened for sexual proficiency. Male rats who displayed consistently vigorous sexual activity were selected for the study.
Pay attention to your vascular health. High blood pressure, high blood sugar, high cholesterol, and high triglycerides can all damage arteries in the heart (causing heart attack), in the brain (causing stroke), and leading to the penis (causing ED). An expanding waistline also contributes. Check with your doctor to find out whether your vascular system — and thus your heart, brain, and penis — is in good shape or needs a tune-up through lifestyle changes and, if necessary, medications.
This is one B team you want to get on pronto: A recent report from Harvard University highlighted a study that has linked low levels of B12 to erectile dysfunction. A causal link hasn’t been nailed down, but the B vitamin is used by every system in the body, particularly in cell metabolism and the production of blood — two essential factors in getting and keeping a quality erection.
While eating magnesium-rich foods or taking a magnesium supplement at the proper dosage is safe for most men, the mineral can interfere or interact with some medications. Discuss the benefits and risks of altering your daily magnesium intake with your doctor, particularly if you take blood pressure medications, diuretics, diabetes medications or antibiotics. Men diagnosed with erectile dysfunction often require changes in other minerals and vitamins or even prescription medication. Ensuring a proper daily intake of magnesium may help maintain healthy erectile function, but magnesium alone is unlikely to cause a significant reduction in ED symptoms. Magnesium levels can also be affected by excess weight, chronic stress and excessive amounts of alcohol. These factors may also be partially responsible for erectile problems.
The human body only contains 2 or 3 grams of zinc at any given time. Zinc is distributed throughout the body in organs, blood, and bones. It can be difficult to diagnose zinc deficiency. While a low blood zinc level does indicate a deficiency, a normal blood level does not necessarily indicate the absence of a deficiency. And examination of the hair for zinc or a zinc taste test (ZTT) may also be used for supportive evidence in the diagnosis of zinc deficiency.