The field of oxidative stress research, as a significant factor of male infertility, is relatively new. However, it has grown rapidly over the past years. It focuses on the balance between oxidants and antioxidants. And as a result, how they affect tissues in living organisms  .
Essentially, Oxidative stress is an imbalance between the production of oxidants (also called free radicals), and the ability of the body to counteract harmful effects through neutralization by antioxidants. Prolonged oxidative stress can damage and lead to death of cells. And this can act as a significant factor of male infertility.
Oxidants or oxidizing agents are by-products generated through several reactions within our body. In sperm, oxidants may lead to protein damage, lipid peroxidation (destruction of lipids), apoptosis (controlled cell death) and DNA damage weakening its fertilization potential .
Antioxidants, our self-defence to oxidation
Antioxidants describe a broad category of substances, which can inhibit oxidation and protect our bodies against the damaging effects of oxidants. Their role is to neutralize oxidants, maintaining the required balance within the cells, to protect them from getting injured (and possibly leading to male infertility)  .
The list of antioxidants is long. Accordingly, it can be divided into those that are:
- produced naturally in our bodies (e.g. glutathione, catalase)
- present in food called dietary antioxidants (vitamins, minerals, carotenoids, polyphenols, etc.).
Berries (strawberries, raspberries, blackberries, cranberries)
Fruits (orange, kiwi, pomegranate, tomatoes)
Leafy greens (kale, spinach, cabbage, romaine lettuce)
Other vegetables (artichoke, broccoli, arugula, bock choy)
Herbs (ginger, cinnamon, turmeric, cumin, cocoa, basil, thyme)
|Tobacco smoking or air pollutants
Excessive consumption of alcohol
Excessive consumption of calories, sugars, refined carbohydrates
Infections (e.g. virus, bacterial infection or other)
Lack of sleep
Presece of a varicocele
So, if you are interested to know more about which dietary compounds can boost your fertility, check our article on fertility supplements here.
How does Oxidative Stress affect human sperm?
While low production of oxidative stress is necessary for normal physiological function, excessive production disrupts the balance between oxidants and antioxidants and brings a number of pathological defects. These defects have been directly associated with impaired sperm function.
Thus, oxidants react with the bio-molecules that compose the sperm cells (lipids, proteins, nucleic acids, sugars) . Damage to the lipids, proteins and sugars may inactivate or cause the death of sperm cells. This is while DNA damage is correlated with poor fertilization rate, high frequency of miscarriage and morbidity in the offspring 
Sperms are vulnerable to oxidation because their membranes contain large amounts of unsaturated fatty acids, a certain category of fatty acids that are very sensitive to oxidation. Moreover, spermatozoa have limited repair mechanisms against the damage caused by free radicals since they do mot have the building blocks to produce new material .
How to fight sperm cell damage
Studies have highlighted that nutrition and supplementation as playing a key role in counteracting the harmful effects on sperm. Especially vitamins and minerals have been found to be vital for the protection against oxidative stress .
Therefore, treatment with antioxidants may increase sperm parameters such as sperm count, sperm motility, and sperm morphology. The biggest source of natural antioxidants are fruits and vegetables. We highly recommend you consume a high amount of fruits such as berries and vegetables such as leafy greens, cruciferous vegetables and tomatoes  .
Furthermore, nother essential route of getting the oxidants is physical activity. Exercising for 45 minutes 3 times per week has been shown to decrease the oxidative stress of the seminal fluid. We therefore highly recommend that you do some sort of physical activity. If you want to know more, have a look at our blog post on how to improve male fertility with exercise
Moreover, it is highly advised to minimise the exposure to lifestyle factors, such as smoking, alcohol consumption, exposure to heat, radiation and other pollutants. These increase oxidative stress and, in turn, lead to sperm damage, decreasing your fertility status.
BOX 1: What is oxidative stress?
|Oxidative stress is a condition associated with an increased rate of cellular damage in our body. It is initiated by oxygen and oxygen-derived oxidants commonly known as reactive oxygen species (ROS). ROS are highly reactive oxidizing agents belonging to the class of free radicals . A free radical is a molecule or element with an unpaired electron that is extremely reactive in order to reach an electronically stable state.This property makes ROS damaging to many living systems as they will readily take hydrogen atoms from lipids, proteins, and DNA to fulfil their electron requirement. ROS can be produced through numerous reactions in the atmosphere, plants, animals and bacteria .
The most common ROS include: