Many men who suffer from erectile dysfunction have problems with their arteries. Garlic contains allicin, which can help improve blood flow, and maintaining efficient blood flow is necessary to maintain an erection.
Erectile dysfunction is usually a physiological problem, and could be a sign of cardiovascular disease. Using garlic (or Viagra) can help with this problem. However, if the cause of ED is psychological, garlic isn't going to help at all.
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