Experts have advised that selenium, a little-known micronutrient, is crucial for brain development in toddlers and boosts their immunity during their formative years amid Nigerias child malnutrition crisis.
Medical professionals say the first five years of a child's life represent a period of extraordinary brain growth, when proper nutrition can influence learning ability, memory, and resistance to illness.
According to the former President, the Nutrition Society of Nigeria, and former Vice-Chancellor of Ambrose Alli University, Prof. Ignatius Onimawo, the importance of nutrients for brain and immune development, malnutrition's effects on early brain development and immunity, and that "the first five years are crucial" for a child's overall growth and learning potential.
In another report, he highlighted that optimal nutrition, including adequate vitamins and minerals, during the first 1,000 days of life can reduce the risk of disease and support longer-term health outcomes, calling for better feeding practices.
Selenium is a trace mineral found in foods such as seafood, eggs, meat, and whole grains, and has emerged as an important contributor to this process.
"Selenium may be needed in very small amounts, but its impact on the developing brain and immune system is significant," experts stated.
"It supports antioxidant defense, thyroid hormone function, and cellular processes that are essential for cognitive development in young children."
Studies have shown that selenium works largely through selenoproteins, enzymes that protect brain cells from oxidative stress caused by free radicals-unstable molecules that can damage developing tissues. This protection is particularly important during early childhood, when the brain is forming new neurons and strengthening connections critical for learning and behaviour.
"Beyond brain development, selenium also plays a key role in immunity. Children with adequate selenium intake tend to have stronger immune responses."
"The early years are critical for a child's growth and development, and without proper nutrition, including micronutrients, children's health and cognitive potential are compromised," said Onimawo.
Nutritionists said it supports the production of white blood cells and enzymes like glutathione peroxidase, which help the body fight infections and reduce inflammation."
Health professionals also point to selenium's role in supporting the thyroid gland, which produces hormones vital for growth and brain maturation. Poor thyroid function in early life, they warn, can negatively affect mental development and physical growth.
While researchers note that studies on the direct link between selenium and cognitive performance in toddlers are still evolving, available evidence suggests that adequate intake during early childhood is beneficial, especially in settings where micronutrient deficiencies remain common.
The good news, experts say, is that selenium can be obtained through a balanced, age-appropriate diet. Foods such as fish including salmon and sardines, eggs, chicken, turkey, whole grains, and fortified products like Peak 456 Growing Up Milk are recognised sources. Brazil nuts are also rich in selenium, though doctors advise caution due to their very high content.
"Parents don't need supplements in most cases. What matters is dietary diversity. A well-planned diet can provide the selenium a toddler needs for healthy brain development and immunity."
Nutritionists advised parents and caregivers who are concerned about their children's diets to consult paediatricians or registered dietitians before introducing supplements, noting that excessive intake of trace minerals can be harmful.
Experts say paying attention to micronutrients like selenium could make a lasting difference.
"A healthy brain starts with what a child eats in the earliest years. Investing in proper nutrition today is an investment in the nation's future."
