A diet high in fruit and grains and low in coffee, alcohol and red meat could boost a man’s fertility during IVF treatment, scientists say.
The study found that a poor diet and obesity can lower sperm concentration and impair their swimming stamina, lowering their chances of fertilising the egg.
Researchers studied 250 men undergoing fertility treatment with their partners, and discovered that those who regularly drank alcohol and ate poorly were less likely to conceive.
Lead researcher Edson Borges, from the Fertility-Assisted Fertilization Center in Sao Paolo said: “The sperm concentration was negatively influenced by body mass index (BMI) and alcohol consumption, and was positively influenced by cereal consumption and the number of meals per day.”
The Brazilian study looked at men undergoing a particular type of fertility treatment called intracytoplasmic sperm injection (ICSI).
Participants were asked to say how often they ate a range of foods, including fruits and vegetables, beans, grains, meat and fish, as well as how much they drank and smoked.
Semen samples were then analysed to assess sperm health and concentration and each couple were monitored during the IVF process
From the speed of their sperm to their partner’s chance of pregnancy, men who drank and had a poor diet were less fertile.
"We talk about having a healthy lifestyle and trying to eliminate any of these things that are bad for health, but I think most of the emphasis tends to be on making sure the woman is as healthy as possible," said Dr. Lynn Westphal, a women's health and fertility specialist at Stanford University Medical Center in Palo Alto, California.
Another recent study found that junk food can render an otherwise healthy man infertile.
Trying to conceive? Boost your chances with these these fertility-boosting diet tips.
Although there is no direct link between refined carbohydrates and infertility, the refining process strips grains of some of the most important fertility-boosting nutrients, such as antioxidants, B vitamins and iron.
Modern methods of food production, involving intensive farming, rob the soil of vital nutrients, so where possible stick to organic produce. Processed foods are packed with additives and preservatives that can upset blood sugar levels and disrupt the body's hormonal balance.
Too much red meat increases the amount of ammonia in the body, which can interfere with the implantation of the egg in the uterus. Red meat can also be detrimental for men as it increases acidity and affects sperm activity; sperm perform better in alkaline conditions.
The animal hormones in dairy products can affect your own hormonal balance. If you balk at the richness of soya milk and can't bear to give up your semi-skimmed, switch to organic dairy products instead as these contain lower levels of hormones.
Giving up alcohol is not strictly necessary until you fall pregnant but it might be worth bearing in mind that Danish research, studying the link between alcohol consumption and fertility, found that alcohol intake had a significant effect on infertility success among women above the age of 30 who drank seven or more drinks a week.
While you don't need to give up your morning coffee, caffeine does constrict the blood vessels, slowing blood flow to the uterus and potentially making it harder for an egg to grab hold. So, if you're having any trouble conceiving, or undergoing IVF treatment, you might want to go easy on the double espressos.
Aside from being packed with vitamins and minerals, fruit and vegetables are packed with antioxidants that attack free-radicals (harmful molecules that can damage the ova, sperm and reproductive organs).
Zinc helps to maintain a healthy menstrual cycle as well as being vital during pregnancy to aid cell division in a developing foetus. Folic acid (Vitamin B6), together with zinc, is essential in the function of female sex hormones. Vitamin B12 is also very important as it maximises the absorption of folic acid. Taking a multi-vitamin tablet designed especially for conception is a good way to ensure you're getting enough of these valuable nutrients. Marmite is also a great source!