From the publication:

Some foods and supplements influence testosterone levels in various animals. The two main mechanisms are the direct increase in testosterone levels or suppression of the decrease in testosterone production due to testicular toxicity. Foods or supplements raise testosterone production in three ways: 1) regulating LH [ luteinizing hormone], the hormone that stimulates the production of testosterone, 2) regulating testosterone synthase in the testis, and 3) regulating testosterone-degrading enzymes. In contrast, suppression of the decrease in testosterone depends on the antioxidant effect of the foods and supplements.

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LH is a gonadotropin that is released by the pituitary glands. Garlic, l-carnitine, selenium, vitamin C, CoQ10, qleuropein, and resveratrol regulate the LH [ luteinizing hormone] secretion. Secreted LH acts on testis receptors and is involved in the synthesis of testosterone from cholesterol. Lactic acid bacteria enhance testosterone production by increasing Leydig cells in the testis. Linoleic acid, maca, and piperin raise testosterone levels by increasing the levels of enzymes involved in testosterone synthesis. These two pathways of testosterone production would be a promising target for treatment. Foods or supplements that have been shown to increase testosterone might act on these pathways. In contrast, testosterone is metabolized to estradiol by aromatase. Chrysin increased testosterone levels by inhibiting aromatase activity. Although detailed mechanistic studies and clinical trials are required to validate the findings, the effects of these foods on testosterone provide potential therapeutic options.