How Can You Personalize Your Supplements?

Micronutrients are vitamins and minerals the body needs to maintain itself — including brain function, blood circulation, a healthy immune system, and every other bodily function. Micronutrients are only needed in relatively small amounts compared to macronutrients (carbohydrates, fats, and proteins), but they are just as vital. Without the proper amount of micronutrients, serious health problems are almost certain, especially in the long term. Diseases that result from or are exacerbated by micronutrient deficiencies can include type 2 diabetes, osteoporosis, cancer, and many others, depending on the specific micronutrients that are missing.[1, 3]

Micronutrient Roles in the Body

Micronutrients are involved in almost everything cells do. In particular, they act as cofactors for certain enzymes. As a result, if someone has a deficiency in a particular micronutrient, the processes that the micronutrient helps facilitate will be compromised. Micronutrients are either water-or fat-soluble, and the body usually retains those that dissolve in fat for a longer period of time. Below is a summary of many of the functions that micronutrients perform:

Protecting against infections

Many micronutrients help defend the body against infections. For example, Vitamin A helps maintain epithelial cells, which cover the body both internally and externally and serve to block microbes while letting nutrients through. In addition, Vitamin D helps create chemicals on the skin and other “barrier” tissues that kill microbes.[4, 5, 7, 11]

Protecting cells from oxidation

Cells naturally produce oxidants, or free radicals, as they produce energy. Oxidants also are produced by the immune system — for example, when it causes inflammation as a result of an infection. These chemicals can damage cells, which can cause cancer and other diseases associated with aging before those diseases otherwise would present themselves. However, certain micronutrients (such as vitamins E and C) can help prevent that by acting as antioxidants.[4, 6, 10]

Maintaining the genome

Micronutrients help the body to make and repair DNA, which in turn helps avoid genetic mutations that can cause cancer and a variety of other diseases.[4, 6]

Producing energy

Vitamins B1-B7 are crucial for helping certain enzymes in the body produce energy from glucose. In addition, the B vitamins plus magnesium, zinc, iron, and manganese are important for generating energy in cell mitochondria. Poorly functioning mitochondria can accelerate aging and promote a variety of diseases.[4, 8, 9]

Maintaining nervous system function

Because micronutrients play such widespread and critical roles in the life of all of the body’s cells, micronutrient deficiencies have been associated with various neurological conditions. For example:

  • The body needs iodine to produce thyroid hormones, and thus iodine deficiencies can cause a variety of thyroid-related conditions. When it comes to the nervous system, fetuses and infants can suffer an irreversible type of brain damage called cretinism if they don’t have sufficient iodine intake.[4]
  • A deficiency in vitamins B6, B9, and B12 can cause elevated levels of the amino acid homocysteine, which in turn has been linked to brain atrophying prematurely and is thought to be a risk factor for Alzheimer’s.[4]
  • Inadequate levels of vitamins B9 and B12 in pregnant women increases the risk of children being born with Spina Bifida, a condition in which the neural tube doesn’t close properly in utero and that usually results in partial paralysis.
  • Inadequate levels of Docosahexaenoic acid (DHA), which is found primarily in the brain and retina, has been associated with a higher risk of vision and neurological problems in infants and dementia in adults.[4]

Assisting with metabolism

Micronutrients play vital roles in metabolism. For example, many vitamins are needed for various chemical reactions within the body, such as riboflavin and niacin for proper functioning of the the electron transport chain, and folic acid for proper transfer of methyl groups. These reactions help ensure that the body can fully utilize macronutrients for energy, nucleic acids, and protein.[10]

Factors Affecting Micronutrient Needs

A variety of life stages, diseases, and other factors can heavily influence micronutrient needs. Some of these are summarized below.


Perhaps it goes without saying, but one’s diet is the largest determinant of the micronutrients being consumed (or not). It is well established that a varied diet that is high in nutritious foods like fruits, vegetables, and organ meats, is necessary to get all the micronutrients the body needs. For many people, such a diet is all that is needed.[17] However, it is worth noting that even whole foods are getting less nutritious over time due to suboptimal farming practices such as overusing the soil, as well as overemphasizing non-nutritive qualities of plants like yield and growing time. In addition, people in one of the categories below might require supplementation of various sorts.


Men and women have different micronutrient needs. For example:

  • Pregnant women need more micronutrients in general, but especially iron and folate — the latter is critical for helping to prevent Spina Bifida and other birth defects.[16]
  • For lactation, a woman needs significantly more vitamins A, E, and C, as well as an increased amount of zinc.[16, 24]
  • Menstruation, pregnancy, and lactation cause women of childbearing age to lose iron at a higher rate than usual. As a result, iron supplements and iron-rich foods are often recommended to combat this problem.[16]
  • Post-menopausal women are prone to calcium loss, and as a result supplements are often recommended.[25]
  • More women are affected by osteoporosis more than men, and thus calcium, boron, magnesium, and silica — all of which are essential for health bones — are especially important for women.[26]
  • Women require more iron than men due to blood loss from menstruation and can benefit from iron supplements.[27]


A person’s individual genetic profile can have an impact in the way that their body processes and metabolizes micronutrients, both from food and supplements. This field is just getting started but already scientists have identified certain genetic code combinations called SNPs (single nucleotide polymorphisms) that we know influence how much of a micronutrient someone needs due to impairment in its metabolism. Read more about this here.


People’s micronutrient needs change as they age.[21] For example, infants are susceptible to various micronutrient deficiencies, including vitamin K, vitamin D, and iron. As a result, infants in the U.S. and other developed nations receive vitamin K supplements when they are born and extra vitamin D during their first year.[16]

In addition, adolescents have unique micronutrient needs due to the significant changes their bodies are going through. For example, calcium, iron, and zinc are essential for sexual maturity and physical growth.[18, 19, 22]

Getting older also increases one’s need for various micronutrients, including vitamins B6, B12, and D. This is a result of changes that come with age, including a decreased ability to absorb vitamin B12 in many older people due to atrophic gastritis, and a decreased ability for the skin to produce vitamin D. By contrast, elderly people with chronic renal failure are prone to vitamin A toxicity and as a result should not take supplements containing it.[16]

Gastrointestinal conditions

Several gastrointestinal conditions can interfere with absorption of many micronutrients in the small intestine, necessitating supplementation. These include, for example, celiac disease, mucosal disease, ileal disease, bacterial overgrowth in the small intestine, chronic cholestasis, and pancreatitis.[16]

Prescription and over-the-counter drugs

Various prescription drugs can also inhibit micronutrient absorption and function, especially when used over the long term. For example:

  • Coumarin can interfere with certain reactions in which vitamin K plays a role, and methotrexate reduces the body’s ability to metabolize folate
  • Antibiotics can deplete folic acid, iron, vitamin A, various B vitamins, calcium, magnesium, potassium, and vitamin K
  • Calcium channel blockers (for high blood pressure) can deplete potassium
  • Selective serotonin reuptake inhibitors can deplete folic acid
  • Statins can deplete vitamin D and CoQ10
  • Oral contraceptives can deplete vitamin B6, folic acid, and magnesium[20]

Lifestyle factors

  • Chronic alcoholism, because misusing alcohol over a long period of time leads to severe depletion of micronutrients, including vitamin deficiency[12]
  • Poor supplementation during parenteral nutrition[13]
  • Serious infections, major surgery, or significant trauma, all of which necessitate more water-soluble vitamins because of the body’s increased energy expenditure in recovery[14]
  • Any condition that results in significant loss of bodily fluids — for example, blood loss causes the body to lose iron, and diarrhea can cause a loss of zinc[15]
  • Smoking, because people who smoke absorb less of several micronutrients, including vitamins C and E and folate[16]
  • Some research indicates that strenuous exercise necessitates a higher intake of certain micronutrients.[29] For example, inflammation from exercise can reduce the body’s ability to absorb iron[28]
  • People under high levels of stress have been shown to benefit from micronutrient supplements[30, 31]
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