What Are Micronutrients?
Micronutrients are the vitamins and minerals your body needs in relatively small amounts to function properly. Unlike macronutrients — carbohydrates, proteins, and fats — they don't supply calories directly. Instead, they act as the regulatory machinery that makes energy metabolism, immune defense, tissue repair, and hundreds of other biological processes possible. See our overview of macronutrients for context on how these two categories work together.
Micronutrients fall into two broad classes:
- Vitamins — organic compounds that can generally be obtained from food. They're subdivided into fat-soluble (A, D, E, K) and water-soluble (the B vitamins and vitamin C) forms.
- Minerals — inorganic elements absorbed from soil and water through plant and animal foods. Major minerals (like calcium and magnesium) are needed in larger quantities; trace minerals (like iron and zinc) are required in smaller amounts.
Because many micronutrients cannot be synthesized by the body in adequate quantities, diet remains the primary source for most people. Gaps in micronutrient intake are more common than many people realize and often go unnoticed for extended periods.
Micronutrients
Vitamins and minerals required by the body in small quantities to support essential physiological processes. They do not provide calories but are critical for metabolism, immunity, and tissue maintenance.
Fat-soluble vitamins
Vitamins A, D, E, and K, which are absorbed alongside dietary fat and stored in fatty tissues and the liver. Because they accumulate in the body, excessive intake over time can potentially cause harm.
Water-soluble vitamins
Vitamins C and the B-complex group, which dissolve in water and are not stored in significant amounts. Excess is generally excreted in urine, making regular dietary intake important.
Trace minerals
Essential minerals needed in very small amounts (typically less than 100 mg per day), including iron, zinc, selenium, and iodine. Small does not mean unimportant — deficiencies can have significant health consequences.
Heme iron
A form of dietary iron found in animal-based foods such as meat, poultry, and seafood. It is generally absorbed more efficiently by the body than non-heme iron from plant sources.
Daily Value (DV)
A reference amount set by regulatory authorities (such as the US FDA) used on nutrition labels to indicate how much of a nutrient a serving provides relative to a general daily intake benchmark.
Key Vitamins: Functions and Food Sources
The table below summarizes the major vitamins, their primary roles, and reliable dietary sources. It is intended as a general reference — individual needs vary based on age, health status, and other factors. Always consult a qualified healthcare professional for personalized guidance.
| Total essential vitamins | 13 (National Institutes of Health, Office of Dietary Supplements) |
| Fat-soluble vitamins | A, D, E, K |
| Water-soluble vitamins | C and 8 B vitamins |
| Most common mineral deficiency globally | Iron deficiency (World Health Organization) |
| Vitamin D synthesis | Also produced by skin via UVB sun exposure |
| Vitamin C enhances absorption of | Non-heme (plant-based) iron (NIH Office of Dietary Supplements) |
| Vitamin | Primary Function | Common Food Sources |
|---|---|---|
| A | Vision, immune function, cell growth | Liver, orange and yellow vegetables, leafy greens, dairy |
| D | Calcium absorption, bone health, immune modulation | Fatty fish, fortified dairy and plant milks, egg yolks; also produced via sun exposure |
| E | Antioxidant protection, immune support | Nuts, seeds, vegetable oils, leafy greens |
| K | Blood clotting, bone metabolism | Leafy green vegetables, fermented foods, some vegetable oils |
| C | Collagen synthesis, antioxidant function, iron absorption | Citrus fruits, bell peppers, strawberries, broccoli |
| B1 (Thiamine) | Energy metabolism, nerve function | Whole grains, legumes, pork, fortified cereals |
| B12 | Red blood cell production, neurological function | Meat, fish, dairy, eggs; fortified plant foods for those avoiding animal products |
| Folate (B9) | DNA synthesis, cell division, fetal development | Leafy greens, legumes, fortified grains, citrus |
Note: This table is not exhaustive. Recommended intake levels are established by public health authorities such as the National Institutes of Health and vary by age and life stage.
Essential Minerals: What They Do and Where They Come From
Minerals support structural roles (bone and tooth formation), fluid balance, enzyme activity, and electrical signaling in nerves and muscles. Understanding which foods supply which minerals makes it easier to build a nutritionally complete eating pattern.
| Mineral | Primary Function | Common Food Sources |
|---|---|---|
| Calcium | Bone and tooth structure, muscle contraction, nerve transmission | Dairy products, fortified plant milks, tofu (calcium-set), leafy greens, sardines with bones |
| Iron | Oxygen transport via hemoglobin, energy metabolism | Red meat, poultry, seafood (heme iron); legumes, tofu, fortified cereals, spinach (non-heme iron) |
| Magnesium | Hundreds of enzymatic reactions, muscle and nerve function, blood sugar regulation | Nuts, seeds, whole grains, legumes, dark chocolate, leafy greens |
| Potassium | Fluid balance, blood pressure regulation, muscle function | Bananas, potatoes, beans, dairy, leafy greens, tomatoes |
| Zinc | Immune function, wound healing, enzyme activity, taste perception | Oysters, red meat, poultry, beans, nuts, seeds, whole grains |
| Iodine | Thyroid hormone production, metabolic regulation | Iodized salt, seafood, dairy, seaweed (amounts vary widely) |
| Selenium | Antioxidant defense, thyroid function | Brazil nuts, seafood, poultry, eggs, whole grains |
Pairing non-heme iron sources with vitamin C-rich foods can meaningfully improve iron absorption — a practical example of how micronutrients interact. To understand how these nutrients appear on product labels, see our guide on reading a nutrition label.
This article is for general informational and educational purposes only and does not constitute medical or dietary advice. Consult a qualified healthcare professional before making changes to your diet, especially if you have a health condition or are in a special life stage such as pregnancy.
The content on this site is provided for informational purposes only and should not be considered a substitute for professional advice. While we strive to provide accurate and up-to-date information, we make no guarantees regarding its completeness or accuracy. Always consult a qualified professional for advice specific to your circumstances before making any decisions.