Oxidative stress is a phenomenon caused by an imbalance between oxidant and antioxidant compounds, resulting from excessive production of free radicals. Free radicals are constantly produced during normal cell function. Maintaining the balance between free radical production and antioxidant defenses is essential for normal body function.
However, excessive production of free radicals can lead to a homeostatic imbalance, oxidation, and damage to cells and tissues. In addition to metabolic processes, excess production can result from various factors such as tobacco consumption, excessive alcohol consumption, ultraviolet radiation, environmental pollution, pesticides, and heavy metals contaminating food.
An imbalanced diet, particularly rich in ultra-processed foods, contributes to an increase in the production of free radicals. Excessive production of free radicals is associated with the aging process and weakening of the immune system. Uncontrolled production of free radicals has been linked to the onset of hundreds of diseases such as cancer, diabetes, obesity, cirrhosis, cardiovascular diseases, and neurological disorders, among others.
Our body has a defense mechanism, which is antioxidants. These function to inhibit and/or reduce the damage caused by free radicals. When our defense fails to prevent the damage caused by oxidants, an imbalance occurs, leading to oxidative stress.
Antioxidants can be enzymatic or non-enzymatic. The enzymatic defense system often depends on the participation of cofactors, such as selenium, iron, copper, zinc, and manganese.
The non-enzymatic defense system includes, especially, antioxidant compounds obtained through diet, namely vitamin C, vitamin E, flavonoids, polyphenols, carotenoids, and glutathione.
It is extremely important to maintain a balanced diet, rich in antioxidants and diverse in vegetables and fruits, as it is the best option for protection against free radicals, reducing the risk of various diseases, preventing premature aging, and promoting a healthy internal defense system.
If you’re unsure where to find these antioxidants, here are their main sources as well as symptoms of their deficiency.
- Selenium
Sources: Broccoli, cabbage, celery, mushrooms, onions, garlic, nuts, seafood, and meat.
Deficiency Symptoms: Hair loss and weakening, brittle nails, skin problems, premature wrinkles, growth issues, arthritis, hypertension, fertility problems, and cataracts.
- Iron
Sources : Seafood, fish, brewer’s yeast, meat.
Deficiency Symptoms: Anemia, general fatigue, muscle fatigue, skin itching, brittle nails, hair loss and fragility, dizziness, headaches, insomnia, difficulty swallowing, cracks in the corners of the mouth, loss of appetite, shortness of breath, rapid heartbeat.
- Copper
Sources: Offal, eggs, seeds, whole grains, seafood, mushrooms, nuts, potatoes, chocolate, coriander, papaya.
Deficiency Symptoms: Anemia, edema, bone and joint problems, cardiomyopathy, pancreatic lesions, arteriosclerosis, Clarice, liver diseases, hypothyroidism, diarrhea, decreased fertility, growth and development problems in children.
- Zinc
Sources: Meat, shellfish, oysters, brewer’s yeast, whole grains, legumes, eggs, and cheese.
Deficiency Symptoms: Growth difficulties, delayed puberty, underdeveloped sexual organs, low sperm density, reduced fertility, impotence, slow healing, eczema, psoriasis, acne, compromised nail and hair growth, loss of taste and smell, reduced appetite, weak immunity, increased risk of infections.
- Manganese
Sources: Shellfish (especially mussels), oysters, and clams, nuts (especially hazelnuts and pecans), legumes, brown rice and whole wheat, seaweed, spinach, pineapple, oats, and tea.
Deficiency Symptoms: Blood sugar level changes, weight loss, dermatitis, nausea, decreased fertility, and carbohydrate metabolism difficulties.
- Vitamin C
Sources: Guava, blackcurrant, citrus fruits, mango, peppers, strawberries, Brussels sprouts, broccoli, potato.
Deficiency Symptoms: Slow healing, dry and scaly skin, fragile hair, hair loss, dry scalp, dry and cracked lips, easy bruising, inflamed and bleeding gums, nosebleeds, muscle and joint pain, irritability, and depression.
- Vitamin E
Sources: Wheat germ oil, avocado, eggs, whole grains, seeds, nuts, bread, fatty fish (salmon, sardines, mackerel, etc.), broccoli.
Deficiency Symptoms: Lack of energy, lethargy, difficulty concentrating, irritability, lack of libido, muscle weakness.
- Flavonoids
Sources: Dried oregano and parsley, green and black tea, chocolate, chickpeas, blueberries, apples, broccoli, soy.
- Beta-Carotene (Provitamin A)
Sources: Dark green leafy vegetables, carrots, sweet potatoes, orange and yellow fruits.
Deficiency Symptoms: Lack of energy, lethargy, difficulty concentrating, irritability, lack of libido, muscle weakness, vision problems, inflamed gums.
The content of this article is for informational purposes only and reflects the personal opinions of the authors. It’s not intended to replace professional advice, whether nutritional or otherwise. Before making any decisions based on what you read here, we recommend consulting with a qualified expert in the relevant field.
