Anyone who’s been to the drug store or supermarket recently knows what they can find in the medicine isle: rows upon rows of multivitamin and individual supplement bottles. The multitude of these supplements alone can be overwhelming for someone looking for a run-of-the-mill daily vitamin. Narrowing your choices by brand is hard enough, but after that, you’ll probably be faced with another decision: men’s or women’s? Does the distinction truly matter?

In general, most multivitamins designed for men and women aren’t really that different. Most types contain the same blend of vitamins and minerals at largely the same doses. The main difference, though, comes down to just a few specific minerals.

What’s the big difference?

The Institute of Medicine has determined the Recommended Dietary Allowance (RDA) and Adequate Intake (IE) levels for most vitamins and minerals. These measurements are the amounts that men and women of different ages need to ingest daily to maintain healthy functionality of the body.

One of the largest differences between men and women’s multivitamins is iron. It is recommended that women take over twice as much iron as men every day if they are premenopausal, since they lose iron through menstruation. However, an excess of iron can build up in the body and leave deposits in your organs, which is why men shouldn’t take the amount of iron recommended to women.

Besides iron, there are usually a few other common differences between men and women’s vitamins. The RDA for Vitamin C is slightly higher for men than for women, although this difference does not usually matter, as most adults receive a higher dose of vitamin C than necessary through their diet. Men also tend to require a slightly higher dose of zinc than women.

Age is also a factor

Age groups also matter when choosing a multivitamin! Not all multivitamins made for males or females will be appropriate for you because different age groups have different dosage recommendations.

For example, multivitamins made for children and the elderly usually have higher levels of micronutrients like calcium that adults below the age of 50 may not need as much of. Elderly men and women also usually need higher levels of vitamin D. Additionally, menopausal women do not require as much iron as women who are actively menstruating do.

What about individual supplements?

Individual vitamin or mineral supplements aren’t usually gendered—if you find that you have a deficiency and your physician recommends that you take a particular individual supplement, you should be able to pick up a standard bottle and take the recommended dosage.

The gendered multivitamins exist because of the blend of vitamins and minerals the have different dosages.

The effects of taking the wrong sex’s multivitamin

Since men and women’s multivitamins are formulated differently, will you get sick if you take the wrong kind? Industry experts say, not usually. Since most of the vitamin and mineral doses are very similar—if not completely the same—taking a daily multivitamin designed for the opposite sex every once in a while won’t hurt you and will still give you the right amount of vitamins and minerals you need each day. However, long-term use may cause some negative effects like mineral build-up, particularly in men who are getting too much iron.

In some cases, men with iron deficiencies may actually be instructed by their physicians to take a woman’s daily multivitamin if they are also in need of other vitamin and mineral support. In other cases, an individual iron supplement would do just fine.

Speak with your doctor

The most important part of choosing a daily multivitamin or supplement to keep you healthy is speaking with your doctor. A physician will be able to tell you what dosage is best for your age, sex and potential deficiency, so you can choose the best option that will not have harmful long-term effects.

It’s also important to remember that multivitamins and supplements are not a replacement for a healthy, well-balanced diet. Getting vitamins and minerals from a pill is usually not enough to keep the average individual happy and healthy, so remember to eat a healthy portion of fruits, vegetables and other vitamin and mineral-rich foods every day.

Next time you are in a store selecting a daily multivitamin, pay close attention to the ingredients and their dosages to make sure you aren’t getting more than you need and speak with your doctor beforehand to identify what sort of supplement is right for you.