Approximately half of all couples who struggle with infertility do so because of a problem with the man's fertility with low sperm count and sperm motility being the most common cause of male infertility. There are several measures a man with a low sperm count can do in order to increase low sperm count, including lifestyle changes such as regular exercise (cycling can negatively impact male fertility), stop smoking, and avoiding tight underwear, whirlpools, and saunas.
Additionally, a man can take several nutritional steps in an attempt to increase his sperm count, motility, and morphology including the following foods in the daily diet.
Zinc supplements and foods
Oysters are high in zinc which is scientifically proven to increase sperm count. Journal of Laboratory Clinical Medicine found that zinc deficiency in men decreased sperm count in four out of five study members, and as soon as they started increasing zinc intake, a sperm count increased.
Folic acid and vitamin C
Spinach is rich in folic acid a vitamin that increases overall sperm count and motility, especially when eaten in conjunction with vitamin C rich foods that promote absorption of folic acid. Men with low levels of folate have more sperm with chromosomal abnormalities.
Eggs, promote male fertility and improve chances of conception, because they are high in vitamin E. Vitamin E is in case of deficiency linked to testicular tissue degeneration. A study on rats proved that vitamin E deficiency causes incomplete spermatogenesis and affects the structural differentiation of epithelial cells of the epididymis — a tube that connects a testicle to a vas deferens in the male reproductive system .
Fruits that are rich in vitamin C, such as citrus fruits, strawberries, cherries, asparagus, snow peas, cooked tomatoes. Study proved that a semen of men with a diet of up to 1,000 mgs of vitamin C (twice daily for a maximum of 2 months) has less clumping than that of their deficient counterparts. The results were impressive:
- the mean sperm count almost tripled (from mean sperm count was 14.3 +/- 7.38 x 10(6) sperms/mL before the vitamin C intake to 32.8 +/- 10.3 x 10(6) sperms/mL (P < .001) after 2 months of vitamin C intake).
- the mean sperm motility doubled (from 31.2 +/- 9.61% to to 60.1 +/- 8.47% (P < .001))
- and mean sperms with normal morphology increased significantly (from 43 +/- 7.87% to 66.7 +/- 4.77% (P < .001))
Food rich in vitamin A
Food rich in vitamin A, including carrots, red peppers, oatmeal, dried apricots, dark green lettuce, broccoli, spinach, sweet potatoes etc. Vitamin A helps grow healthy sperm, and deficiencies in vitamin A in men are linked to lowered fertility due to sluggish sperm. Vitamin A helps regulate germ cell differentiation and has a postitive effects on the generation of both the cycle of the seminiferous epithelium and the spermatogenic wave.
Nuts are rich in arginine and selenium
Scientists recommend eating choosing walnuts and almonds because they are both rich with arginine, an amino acid that increases sperm production and blood flow. Blood vessels need arginine to dilate and form an erection. Supplementing with arginine has been shown to help men with erectile dysfunction in some studies. Increased blood flow is related to stronger erections, which, though unrelated to sperm count, is correlated with higher rates of fertilization. 
On the other hand, Brazil nuts are high in selenium that is an essential mineral for developing normal sperm and in increasing sperm motility. A relatively large study proved that supplemental Selenium with a combination of vitamin E improves semen quality and has beneficial and protective effects, especially on sperm motility.
Boost chromium levels
Whole grains increase chromium levels, thereby increasing your sperm count; studies prove that low chromium levels are correlated with decreased sperm count. Chromium deficient rats had 25% lower conception rate and 50% lower sperm count. 
Make sure to include DHA and other essential omega-3 fatty acids into your diet because they help improve blood flow to the genitals and increase sexual function. And not only that, a study found that a certain omega-3 fatty acid is necessary to construct the arch that turns a round, immature sperm cell into a pointy-headed super swimmer with an extra long tail. Yep, the DHA is "Bob-the builder" in the sperm-cell architecture. The study proves that DHA is needed to fuse the building blocks of the acrosome together. Yes, you've guessed it — the acrosome is critical in fertilization because it organizes a variety of enzymes that sperm use to penetrate an egg.
DHA and other essential omega-3 fatty acids are found in salmon, sardines, anchovies, walnuts, arugula, crab, shrimp, flax, chicken, fish oil, etc.