The 14 most clinically important micronutrients to track daily are: Vitamin D, Iron, Calcium, Vitamin C, Magnesium, Vitamin A, Vitamin E, Vitamin K, Vitamin B12, Folate, Potassium, Zinc, Selenium, Sodium, and Omega-3 fatty acids. Each has a gender- and age-specific Recommended Dietary Allowance (RDA), and deficiency in any one of them has documented health consequences backed by peer-reviewed research.

Calorie counting dominates the conversation about nutrition. Macronutrients (protein, fat, carbohydrate) come second. Micronutrients — vitamins and minerals — are often treated as an afterthought, something handled by eating "a varied diet."

The data challenges this assumption. Research by Passarelli et al. (2024) in The Lancet Global Health, modelling dietary data across 185 countries, found that a significant majority of the global population fails to meet RDAs for at least one essential micronutrient. The most common deficits include iodine, vitamin E, calcium, and iron — nutrients found in foods most people believe they eat regularly.

The problem intensifies during weight loss. Zhang et al. (2024) in Frontiers in Nutrition demonstrated that caloric restriction specifically increases the risk of micronutrient deficiency, because eating less food means less opportunity to meet micronutrient targets — even when food choices are deliberately healthy. Awuchi et al. (2020) in the International Journal of Food Sciences reviewed the health consequences of deficiency across vitamins and minerals, confirming that meeting specific daily requirements is "critical for preventing deficiency diseases and maintaining optimal physiological and immune functions."

What it does: Regulates calcium absorption, supports bone density, immune function, and mood regulation.

Why track it: Holick & Chen (2008) in The American Journal of Clinical Nutrition described vitamin D deficiency as "a worldwide epidemic" associated with increased risk of cancers, autoimmune diseases, hypertension, and infectious diseases. Very few foods naturally contain significant vitamin D; sunlight exposure (which triggers skin synthesis) is the primary source for most people — and is insufficient in northern latitudes for much of the year.

RDA: 600 IU/day for adults 18–70; 800 IU/day for adults over 70 (higher in clinical guidelines for deficient individuals).

What it does: Essential for haemoglobin formation — the protein in red blood cells that carries oxygen throughout the body.

Why track it: Strauss et al. (2018) in Health and Quality of Life Outcomes found that iron deficiency anaemia is "significantly associated with greater fatigue, reduced physical performance, and more depressive symptoms." Iron needs differ substantially by sex: menstruating women have significantly higher needs than men or post-menopausal women, making it a particularly important micronutrient for women in their reproductive years.

RDA: Women (19–50): 18 mg/day. Men (19+) and women (51+): 8 mg/day.

What it does: Builds and maintains bone and teeth; essential for muscle contraction, nerve signalling, and blood clotting.

Why track it: Most people associate calcium primarily with childhood bone development, but it remains critical in adulthood — particularly for women, where low calcium intake in midlife is a key risk factor for osteoporosis. Anderson et al. (2016) in the Journal of the American Heart Association found that while dietary calcium intake may be protective against cardiovascular disease, calcium from supplements may carry elevated risk — making food-based calcium tracking particularly valuable.

RDA: Adults 19–50: 1,000 mg/day. Women 51+: 1,200 mg/day. Men 71+: 1,200 mg/day.

What it does: Antioxidant; supports immune cell function, collagen synthesis, and iron absorption.

Why track it: Carr & Maggini (2017) in Nutrients established that vitamin C "contributes significantly to immune defence by supporting various cellular functions of both the innate and adaptive immune systems." It also enhances non-haem iron absorption — meaning if you're eating plant-based iron sources, pairing them with vitamin C substantially improves uptake.

RDA: Women: 75 mg/day. Men: 90 mg/day. Smokers: add 35 mg/day.

What it does: Involved in over 300 enzymatic reactions — energy production, protein synthesis, muscle and nerve function, blood pressure regulation.

Why track it: Veronese et al. (2020) in the European Journal of Nutrition concluded from an umbrella review of systematic reviews that "adequate magnesium intake is inversely associated with the risk of developing hypertension, cardiovascular diseases, and type 2 diabetes." Magnesium is found in whole grains, nuts, seeds, and leafy greens — foods that are underrepresented in most Western diets.

RDA: Women: 310–320 mg/day. Men: 400–420 mg/day.

What it does: Maintains vision (especially night vision), supports immune function, skin integrity, and cell growth.

Why track it: Villamor & Fawzi (2005) in Clinical Microbiology Reviews found that vitamin A supplementation in children produced "large reductions in mortality and morbidity" by maintaining immune responses and epithelial integrity — confirming its critical role in immune health across the lifespan. Adults eating limited vegetables, particularly orange and yellow produce and leafy greens, are at risk of insufficient intake.

RDA: Women: 700 mcg RAE/day. Men: 900 mcg RAE/day.

What it does: Fat-soluble antioxidant; protects cell membranes from oxidative damage; supports immune function.

Why track it: Lonn et al. (2005) in JAMA, studying long-term vitamin E supplementation, found it did not prevent cancer or cardiovascular events and may increase heart failure risk at high doses in at-risk populations — an important finding that underscores the value of tracking dietary intake rather than supplementing indiscriminately. Meeting needs through food (nuts, seeds, vegetable oils) is the recommended approach.

RDA: Adults: 15 mg/day.

What it does: Essential for blood clotting and bone metabolism; regulates calcium deposition in bones versus arteries.

Why track it: Van Ballegooijen et al. (2017) in the International Journal of Endocrinology found that vitamins D and K work synergistically — optimal levels of both support bone strength and cardiovascular health by regulating where calcium is deposited in the body. Vitamin K is found primarily in leafy greens (K1) and fermented foods (K2); deficiency is common in people who eat few vegetables.

RDA: Women: 90 mcg/day. Men: 120 mcg/day.

What it does: Required for nerve function, DNA synthesis, and red blood cell formation.

Why track it: Green et al. (2017) in Nature Reviews Disease Primers confirmed that B12 deficiency "is linked to an increased risk of cognitive impairments, neurological disorders, and anaemia." B12 is found almost exclusively in animal-derived foods — making it the micronutrient most likely to be deficient in vegans and vegetarians, who should track and supplement it carefully.

RDA: Adults: 2.4 mcg/day (note: needs may be higher as absorption decreases with age).

What it does: Essential for DNA synthesis and repair; critical for cell division, particularly during pregnancy.

Why track it: The US Preventive Services Task Force (2023) in JAMA confirmed that folic acid supplementation is "highly effective and recommended for preventing serious birth defects, specifically neural tube defects" — making it the single most important micronutrient to track for women who are pregnant or planning pregnancy. Beyond reproduction, folate supports cardiovascular health and mental wellbeing in all adults.

RDA: Adults: 400 mcg DFE/day. Pregnant women: 600 mcg DFE/day.

What it does: Regulates fluid balance, supports muscle contraction and nerve signalling, offsets the blood pressure-raising effect of sodium.

Why track it: Aburto et al. (2013) in BMJ, in a systematic review and meta-analysis, found that "increased potassium intake significantly reduces blood pressure in adults with hypertension and lowers overall cardiovascular risk." Most adults consume substantially less potassium than recommended, while consuming excess sodium — a combination that amplifies cardiovascular risk.

RDA (Adequate Intake): Women: 2,600 mg/day. Men: 3,400 mg/day.

What it does: Supports immune cell function, wound healing, DNA synthesis, and taste and smell perception.

Why track it: Prasad (2008) in Molecular Medicine established that "zinc deficiency rapidly diminishes both antibody- and cell-mediated immune responses." Zinc is found in meat, shellfish, legumes, and seeds — with plant-based zinc being less bioavailable than animal-based zinc due to phytate content, meaning plant-focused eaters may need higher total intake.

RDA: Women: 8 mg/day. Men: 11 mg/day.

What it does: Regulates fluid balance and nerve function — essential in the right quantities, harmful in excess.

Why track it: Gupta et al. (2023) in JAMA demonstrated in a crossover trial that "a reduction in dietary sodium intake leads to a significant decrease in systolic blood pressure." The WHO recommends under 2,000 mg/day; most adults in high-income countries consume 3,400–4,000 mg/day. Unlike most micronutrients where the goal is to meet the minimum, sodium is one where most people need to reduce rather than increase intake.

WHO Recommendation: Less than 2,000 mg/day (5g of salt).

What they do: Reduce inflammation, support cardiovascular function, brain health, and eye health.

Why track them: Manson et al. (2019) in the New England Journal of Medicine found that "higher intake of marine omega-3 fatty acids is associated with reduced risks of cardiovascular disease outcomes and mortality." Omega-3s are found primarily in oily fish (salmon, mackerel, sardines), and to a lesser extent in walnuts and flaxseed (though plant-based omega-3 is ALA, which converts to EPA/DHA at low efficiency).

Adequate Intake: Women: 1.1 g ALA/day (or equivalent EPA/DHA). Men: 1.6 g ALA/day.

What it does:
Selenium is a trace mineral your body needs for antioxidant defense, thyroid hormone metabolism, immune function, fertility, and DNA protection.

Why track it:
Selenium is small but powerful. It is a core part of selenoproteins, including enzymes like glutathione peroxidase, which help protect cells from oxidative damage. It also plays a major role in thyroid function because the thyroid uses selenium-containing enzymes to activate and regulate thyroid hormones. The NIH notes that selenium is important for reproduction, thyroid hormone metabolism, DNA synthesis, and protection from oxidative damage and infection.

It is especially worth tracking because selenium has a narrow useful range. Too little can impair thyroid and immune function. Too much can become toxic. This makes it different from nutrients like vitamin C, where excess is usually less concerning.

RDAs are not one-size-fits-all. Iron needs for a 25-year-old woman are more than double those of a man of the same age. Calcium needs increase after 50 for women. Vitamin D needs rise with age. Folate needs spike dramatically during pregnancy.

Forkd applies gender- and age-specific RDA targets across all 14 tracked micronutrients, so your daily progress reflects what your body needs — not an averaged population figure.

Do I need to hit 100% of every micronutrient every day?

Not necessarily — RDAs are designed to meet the needs of nearly all healthy individuals, so they include a margin above the average requirement. Consistently hitting 70–80% of your RDA across most micronutrients over time is more meaningful than perfect daily compliance. Persistent shortfalls in specific nutrients (particularly iron, vitamin D, and B12) are the ones worth investigating.

Can I get all micronutrients from a typical diet?

For most people eating a varied whole-food diet including meat, fish, dairy, vegetables, legumes, and whole grains — yes, most micronutrient needs can be met through food. The exceptions are vitamin D (hard to get from diet alone without sunlight) and B12 for vegans (requires supplementation). Tracking reveals where your specific diet has blind spots.

Should I take a multivitamin?

The evidence for multivitamins as a general health intervention is mixed. For specific deficiencies, targeted supplementation is more effective than broad-spectrum multivitamins. Tracking dietary micronutrient intake first allows you to identify actual gaps rather than supplementing without information.