Trace nutrients needed to meet the growth needs of children after 12 months
All nutrients in the body are important for growth and development in children because they support how energy is produced and how new cells are made to increase muscle and bone size, strength and activity. Some micronutrients (also called trace nutrients, because the body doesn’t need very much) are less commonly present in nutrient supplements or fortified foods for children, but they are critical for growth and development, and help prevent undernutrition. The WHO has found that around 45% of child health problems are due to undernutrition , from simply not providing enough of the right nutrients, and these can be prevented using comprehensive nutrient sources.
Some less common nutrients are listed below. These have different support (helper) roles :
- Vitamin K: helps to mobilize and deposit calcium into new bones as they grow longer and increase in hardness 
- Biotin (vitamin B7): used in special processes within cells that produce energy for growth 
- Vitamin B5: used to convert fats, carbohydrates and protein into energy for growth
- Choline: used to make fatty cell membranes in the body. Membranes are what holds tissues and organs together and they increase in amount as kids’ bodies get bigger
- Selenium: protect against infections that slows down growth rate
- Manganese: used in the formation of bone mineral
- Molybdenum: converts protein from diet into amino acids, that are used for growth of muscles and other tissues 
- Chromium: helps with converting glucose into energy for growth
- Copper: used for the production of new cells, including red blood cells
- Potassium: controls muscle function and movement, which stimulate skeletal development
Why are these substances important to children?
- As seen from their roles above in relation to growth, these nutrients participate in a lot of different processes that control growth at the cellular level. This includes making energy from macronutrients or using that energy to build new tissue, cell by cell.
- In the case of energy, a problem with energy production basically means slowing down of growth, leading to stunting and wasting.
- Many of these nutrients are considered essential when children have a diet that is not adequate enough, such as for children with specific illnesses, infections or ongoing health problems 
How do these nutrients affect children and how do they work together?
- Deficiencies in one or more of these nutrients can also cause health problems, because they are involved in many other aspects of children’s body functions, including immunity, digestive health, brain and eye health.
- These substances protect children’s bodies against the deficiencies mentioned above, which allows their bodies to grow and develop optimally, and prevent times when growth halted or delayed
- Some of them work together in the following ways
- Copper, selenium, manganese: support antioxidant processes work in the immune system to protect against illnesses and infections, which in turn, protects growth and development. They also protect brain, eye and gut function.
- Vitamin K, manganese, potassium: contribute to the stimulation of bone formation and strength, through different pathways
- Chromium, biotin, vitamin B5, molybdenum: help the body convert macronutrients from food into energy
- Choline, potassium: help to support healthy brain and nerve activity and reflexes
Food sources of these substances
- Vitamin K: fermented foods, like Natto and Kefir; kale
- Biotin: eggs, dairy milk, oats, cereal
- Vitamin B5: mushrooms, dairy milk, chicken
- Choline: eggs, fish, chicken
- Selenium: tuna, brown rice, brazil nuts
- Manganese: pineapple, sweet potato, berries
- Molybdenum: lentils, peas, beans
- Chromium: beef, broccoli, rice
- Copper: seafood, leafy vegetables, rice
- Potassium: banana, mushrooms, rice
- Protein sources: protein is not just important on its own for growth of muscle and body size. Meats, fish and dairy foods contain almost all of the abovementioned nutrients at varying levels. Children who are not consuming enough protein, like in a vegan family/group or in a rural area with mostly plant based or traditional diets may be deficient in many of these nutrients
- Seeds and nuts: these may sometimes cause allergies, but small amounts of seeds and nuts contain many of the minerals above, and may complement a varied diet
- Leafy vegetables: these are also sources of minerals, however on their own they can also remove minerals from the body if there is not enough protein consumed