Daily Vitamin Intake For Adults You Must Know!



Updated on 4/16/2024
Martin AlvarezBy Martin Alvarez
Nutritionist/Dietitian Professional Guide
Learn More about Martin Alvarez

You are on what appears to be a straightforward task as you make your way through the aisles of the pharmacy: to get some vitamins. On the other hand, merely casting your eyes over the label of a bottle may cause you to reach for the nearest dictionary. On many different items, you'll see an alphabet soup consisting of abbreviations like "RDA" and "DV," to name just two instances. But don't despair. We'll help you demystify supplement guidelines.

What The Figures Really Mean



You can better understand how much of a specific vitamin or mineral you should take in by paying attention to the terminology used on supplement labels and websites. For instance, the following are some recommendations that the Institute has made for Medicine:

The Recommended Dietary Allowance (RDA) and the Enough Intake (AI) are the amounts of a vitamin or mineral that you need to consume on a daily basis in order to maintain your health and receive adequate nutrition. They are geared specifically toward women, males, as well as certain age groups.

Daily Vitamin Intake

Daily Vitamin Intake

The Tolerable Upper Intake Level, also known as the UL, is the highest quantity of vitamins and minerals that a person can consume on a daily basis without running the risk of experiencing an overdose or major adverse effects. When it comes to particular nutrients, the more the amount by which you exceed the UL, the greater the likelihood that you will run into issues.

In addition to the RDA and the UL, the Food and Drug Administration employs the third method to determine the appropriate levels of nutrients in the human diet:
On labeling foods and supplements, the only measurement that will be listed is the DV or the daily value. This is because there is a restriction on the amount of space available, and only one reference number can be listed. A diet consisting of 2,000 calories per day should provide you with this quantity of vitamins or nutrients in order for you to enjoy the best possible health. There are situations when the DV and the RDA are the same.

Remember that the RDA and the DV are both designed to help you acquire the nutrients you need to prevent disease and avoid difficulties that might be caused by a lack of nutrition, despite the details being different for each of them.

How Much Is Considered Excessive?



How do you tell when it is safe to take more than the recommended daily allowance (RDA) or daily value (DV) of a supplement when using large amounts of some supplements, which can pose risks?

To find out what the UL (tolerable upper intake level) of a nutrient is, one option is to check it up. You can safely consume a dose of several vitamins and minerals that is far greater than the recommended daily allowance (RDA) or the daily value (DV) without going anywhere near the maximum allowed.

For instance, a typical person can consume more than 50 times the recommended daily allowance (RDA) of vitamin B6 without exceeding the maximum allowable amount. However, for some persons, increased levels of B6 are associated with the development of symptoms of nerve discomfort. Therefore, you should constantly exercise extreme caution. The following are some things that should be kept in mind:

Some dietary supplements come with a higher risk than others. In the case of several vitamins and minerals, the maximum allowable dosage is relatively close to the RDA. Therefore, it is simple to consume too much of it. For instance, a man who consumes slightly more than three times the recommended daily allowance (RDA) of vitamin A would receive more than the permitted amount. It is possible for dangerous levels of vitamin A and other fat-soluble vitamins like E and K to accumulate in the body if the vitamin is taken in excessive amounts. Iron and selenium are two minerals that are commonly found in supplements that are also known to be dangerous.



Dietary supplements are intended to be taken in addition to one's regular diet. Consuming medications is not the solution to maintaining a healthy lifestyle. According to dietary specialists, the best way to ensure that your diet is complete and balanced is to also take nutritious supplements. Certain individuals choose to take multivitamins containing minerals as a form of nutritional insurance.

In many cases, the UL represents the upper limit for all potential sources of a nutrient. It is possible to include the quantity you get from food as well as the amount you obtain from supplements. Therefore, while determining whether or not you have met the UL for a specific nutrient, you must consider the food you have consumed.
On food nutrition labels or on the bottle of your vitamin supplement, you won't find the UL. It's not a number that most people are familiar with. However, it can be found on websites run by the government. At the conclusion of this piece, you'll get a comprehensive list of nutrients along with their ULs.

Most dietary supplements do not have a UL, RDA, or DV listed for them. Only a small number of the vitamins and supplements on the market have had their recommended dosages established by the government. Most supplements sold in stores don't have an established optimal or maximum dosage, and the specialists don't know why.

If consumed in quantities considered unhealthy, numerous nutrients can be harmful. Stay away from the UL for any vitamin. In addition, before taking any supplements, you should consult your primary care physician if you have a preexisting medical problem. They will be able to inform you of any potential adverse effects or interactions with other medications that you take.

RDAs And ULs For Vitamins And Minerals Are Listed In The Table



The Institute of Medicine has established maximum safe levels for twenty-four different nutrients. This table is only for adults who are at least 19 years old. Because women who are pregnant or breastfeeding have distinct nutritional needs, this does not apply to them because their needs are different.

or Mineral
Recommended Dietary Allowance (RDA) or Adequate Intake (AI)
Nutrients with AIs are marked with an (*)
Upper Tolerable Limit (UL)
The highest amount you can take without risk
BoronNot determined20 mg/day
  • Age 19-50: 1,000 mg/day.
  • Women age 51+: 1,200 mg/day.
  • Men age 71+: 1,200 mg/day.
  • Age19-50: 2,500 mg/day.
  • Age 51 and up: 2,000 mg/day.
  • Age 19-50: 2,300 mg/day
    Age 50-70: 2,000 mg/day
    Age 70 and older: 1,800 mg/day
3,600 mg/day
(Vitamin B complex)
Women: 425 mg/day *
Men: 550 mg/day *
3,500 mg/day



900 micrograms/day10,000 mcg/day
FluorideMen: 4 mg/day *
Women: 3 mg/day *
10 mg/day

Folic Acid


400 mcg/day


1,000 mcg/day

This applies only to synthetic folic acid in supplements or fortified foods. There is no upper limit for folic acid from natural sources.



150 mcg/day1,100 mcg/day

Men: 8 mg/day
Women age 19-50: 18 mg/day
Women age 51 and up: 8 mg/day
45 mg/day
Men age 19-30: 400 mg/day
Men age 31 and up: 420 mg/day
Women age 19-30: 310 mg/day
Women age 31 and up: 320 mg/day

350 mg/day

This applies only to magnesium in supplements or fortified foods. There is no upper limit for magnesium in food and water.


Men: 2.3 mg/day *
Women: 1.8 mg/day*
11 mg/day

45 mcg/day 2,000 mcg/day

Not determined 1 mg/day
700 mg/dayUp to age 70: 4,000 mg/day
Over age 70: 3,000 mg/day



55 mcg/day400 mcg/day

Age 19-50: 1,500 mg/day *
Age 51-70: 1,300 mg/day *
Age 71 and up: 1,200 mg/day *
2,300 mg/day

Not determined 1.8 mg/day
Vitamin A

Men: 900 mcg/day
Women: 700 mcg/day
3,000 mcg/day

Vitamin B3 (Niacin)


Men: 16 mg/day
Women: 14 mg/day
35 mg/day
This applies only to niacin in supplements or fortified foods. There is no upper limit for niacin in natural sources.
Vitamin B6

Men age 19-50: 1.3 mg/day
Men age 51 up:1.7 mg/day
Women age 19-50: 1.3 mg/day
Women age 51 up: 1.5 mg/day
100 mg/day
Vitamin C

Men: 90 mg/day
Women: 75 mg/day
2,000 mg/day
Vitamin D (Calciferol)

Age 1-70: 15 mcg/day
(600 IU, or international units) *
Age 70 and older: 20 mcg/day (800 IU) *
100 mcg/day
(4,000 IU)
Vitamin E

22.4 IU/day
(15 mg/day)

1,500 IU/day
(1,000 mg/day)

This applies only to vitamin E in supplements or fortified foods. There is no upper limit for vitamin E from natural sources.


Men: 11 mg/day
Women: 8 mg/day
40 mg/day