1Cellular oxidation and oxidative stress
Cellular respiration is the process by which cells break down food molecules to obtain energy (ATP). 95% of the ATP produced is generated in the mitochondria.
Mitochondria present a paradox: they are not only the largest producer of ATP (the energy source) in cells, but they are also the largest source of free radicals. When mitochondria produce the ATP our body needs to function, they also produce free radicals that damage and age our body. These free radicals are atoms with an unpaired electron in their composition, and in an attempt to achieve stability, they steal electrons from other atoms, which then become free radicals themselves. This chain reaction leads to cell destruction, making free radicals one of the main culprits behind premature aging and the development of degenerative diseases such as arteriosclerosis, diabetes, cancer, cataracts, inflammatory conditions, and Alzheimer's. However, having a small amount is perfectly normal and poses no health risk, as the body has the necessary mechanisms to keep them under control. The problem arises when these few free radicals generate new ones, and the number begins to grow to such an extent that our antioxidant defenses are overwhelmed. We then enter a dangerous state for the integrity of the cell, putting its very life at risk: oxidative stress.
2Antioxidants and free radicals: eternal enemies
An excess of free radicals causes an imbalance in the only substances capable of counteracting their numbers: antioxidants.
Antioxidants, along with the immune system, form the two lines of natural defense for our body. They are active substances that include enzymes, vitamins, minerals, phytonutrients, and natural products. Their role is to selflessly donate the electron that the free radical needs to achieve its desired stability, thus neutralizing it and preventing it from circulating freely throughout the body and its harmful effects on health.
Antioxidants and free radicals are therefore antagonistic forces in a perpetual struggle upon which the life of the cell depends. And when free radicals begin to win this battle, the deficiency of antioxidants must be compensated for, either by the body itself or through external assistance. Let's see how our body prepares its antioxidant defenses against free radicals.
3Antioxidant defense systems
Our body has two natural ways to combat excess free radicals and the oxidative stress they cause:
1. Endogenous form, through a series of enzymatic systems present in the human body. Some of the best-known and most studied enzymes are superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase, and thioredoxin (TRX), among others.
Although quite effective, endogenous natural defenses usually need the support of exogenous antioxidants to neutralize as many free radicals as possible.
2. Exogenous form, that is, from the outside, through dietary antioxidants present in food and nutritional supplements. These are substances that are part of everyday foods and can prevent the adverse effects of reactive oxygen species on normal human physiological functions.
These antioxidant substances are found primarily in the plant world, so the first recommendation to combat excess free radicals and their harmful health consequences is to increase the consumption of plant-based foods at the expense of animal-based foods.
4Plant-based antioxidants: the power of plants
Once again, nature offers us the full preventative and curative power of plants for a healthy purpose: to fight premature aging and degenerative diseases caused by an excess of free radicals. Many plant-based antioxidants are present in foods.
Among them, the following stand out:
• Flavonoids: such as the anthocyanins in red and purple fruits (strawberries, blackberries, blueberries, pomegranate, papaya), the citroflavonoids in citrus fruits (oranges, lemons, grapefruit), and the catechins in green tea.
• Tannins present in grapes and red wine.
• Isoflavones (genistein, daidzein) present in soy, flax seeds, and rye.
• Beta-carotene: natural pigments capable of being converted into vitamin A when it is required for any of its functions, including its antioxidant function. It is found in foods such as carrots, pumpkin, melon, mango, spinach, and spirulina algae.
• Vitamin E: present in virgin olive oil and other vegetable oils, avocados, nuts, and spirulina algae.
• Vitamin C: present in citrus fruits, tomatoes, bell peppers, tropical fruits (guava, papaya), spinach, broccoli, fresh soybeans, grapes, and spirulina algae.
• The mineral selenium: present in some nuts and coconut.
• The mineral zinc: present in wheat germ, nuts, and whole grains.
As we can see, plant-based foods offer us a wide range of antioxidants with excellent properties. However, their consumption is often quite low, and many of these foods no longer contain the expected amounts of vitamins, minerals, and phytonutrients due to poor soil quality caused by overexploitation. This is when antioxidant nutritional supplements become an essential ally against the growing threat of free radicals.
5Nutritional supplements: when to start the battle and what weapons to use?
There isn't really a specific age at which we should start taking antioxidant supplements. It depends on the degree of aging and the risk factors (smoking, stress, excessive sun exposure, living in highly polluted areas, etc.) to which we are exposed. However, generally speaking, almost everyone should start taking some kind of supplement after the age of 35. The antioxidant category is one of the most diverse in the supplement market. This makes choosing a specific product even more complicated.
To make this task easier, it's advisable to consider a few factors:
• The selection of the raw materials that make up the compound.
• The dosage of the raw materials, that is, the percentage of them or their active ingredients with antioxidant capacity that the product contains.
• The ORAC value, which is an index that measures the total amount of antioxidant substances contained in a food or supplement. The USDA (United States Department of Agriculture) recommends a minimum of 3,000-5,000 ORAC units to counteract the harmful effects of excess free radicals.
• Ensure that supplements comply with Good Manufacturing Practices (GMP) as a guarantee of safety and quality in their production.
