Table of Key Nutrients


 Table of 20 key nutrients


Adult RDA or AI*

Common therapeutic range  (daily intake)

Dietary considerations concerning adequacy of average daily intake


Key minerals


1000–1200 mg

800–1200 mg

Typical diet is inadequate, averaging 500–850 mg.



1250 mg 9–18 yrs
700 mg adults

800–1200 mg

Inadequate intake is rare except in elderly and malnourished. Excess intake common with use of processed foods and soft drinks — ~1500 mg/day in men and ~1025 mg/day in women.



420 mg adult males
320 mg adult females

400–800 mg

Intake generally inadequate among all ages, sexes, and classes except children under the age of 5; 40% of total population and 50% of adolescents consume 66% of RDA; and 56% of all Americans have intakes below Estimated Average Requirement (EAR).



30–35 mcg, adult males
20–25 mcg, adult females 

200–1000 mcg 

Common intake in the US is 50 mcg or lower.


(Silicon — Si)

No values set to date

5-20 mg

Intake significantly higher in men (30–33 mg/day) than in women (~25 mg/day), yet generally suboptimal. Silica is the first element to go in food processing.



11 mg adult males
8 mg adult females

12–30 mg

Average intake is 46–63% of RDA. Marginal zinc deficiency is common, especially among children.



2.3 mg (AI) adult males
1.8 mg (AI) adult females 

2–10 mg

Intake generally inadequate, at 1.76 mg adolescent girls; 2.05 mg adult females; and 2.5 mg adult men.



900 mcg adults
(0.90 mg)

1–3 mg

75% of diets fail to contain RDA. Average daily intake is below the RDA.



No RDA established

3–5 mg

Common daily intake is only 0.25 mg, to possible optimum of 3.0 mg.



4700 mg adults

4000–6000 mg 

Adult intake averages 2300 mg for women and 3100 mg for men.



No RDA established

3–30 mg (supplements)
up to 680 mg (in medications)

Daily dietary intake thought to vary from 1 mg to more than 10 mg.


Key vitamins

Vitamin D

600 IU 1-70 yr
800 IU >70 yr

800–2000 IU and up, as needed

Numerous experts say that a billion people worldwide are deficient today. Deficiency is especially common among people who are elderly, dark skinned, and those with little UV sunlight exposure. A simple, inexpensive blood test for 25(OH)D is the best way to determine vitamin D status and need.


Vitamin C

90 mg adult males
75 mg adult females

Oral 500–3000 mg (and upward to bowel tolerance), as needed.

Average daily intake is about 95 mg for women and 107 mg for men. Based on US survey of nearly 9000 people, intake for 31% of population is below Estimated Average Requirement (EAR).


Vitamin A

2997 IU adult males
2331 IU adult females

5000 IU or less 

44% of US population has intake below EAR.


Vitamin B6

1.3–1.7 mg adult males
1.3–1.5 mg adult females 

25–50 mg

Studies indicate widespread inadequate vitamin B6 consumption among all sectors of the population; >50% of population consume 70% RDA.


Folic acid/folate
(vitamin B9)

400 mcg adults
(0.4 mg)

400–1000 mcg
(0.4–1 mg)

Inadequate intake common among all age groups; although improving with food fortification, 49% of participants in NHANES survey had intakes below Estimated Average Requirement (EAR).


Vitamin B12

2.4 mcg adults

150–1000 mcg 

Up to 40% of US population have marginal B12 status. Older people and vegans are especially at risk.


Vitamins K1 and K2

120 mcg adult males
90 mcg adult females
No recommended intake

250–1000 mcg
45–180 mcg MK-7 (menaquinone-7)

Averages 45–150 mcg, which is well below the recommended AI.
Average US intake 9–12 mcg (if any).


Other nutrients


Should comprise minimum of 7% total calories. General recommendation is not to exceed 30% of caloric intake.

20–30% of total calories is perhaps more ideal

Average American consumes ~33% of his/her calories in fat. Consumption of essential fatty acids (EFA’s), however, is frequently inadequate.



0.8 g/kg per day adult males and females
125-lb person = 45 g
175-lb person = 63 g
56 g adult males
46 g adult females

1.0–1.5 g/kg

Daily intake commonly exceeds 100 g, but the elderly and some women often have very deficient intake. Higher protein intake should be balanced with higher RDA level potassium intake from food sources.