What Vitamins Do You Really Need to Take?

"Um, exactly how many vitamins do you take a day?" my friend asked recently as she peered into my medicine cabinet and read the labels of the dozen or so vitamin bottles.

"A ton: a multi-vitamin, fish oil, vitamin b12, vitamin d..." I started.

"It's not healthy for you to take so many vitamins," she interrupted.

I disagree: I take a regimen of about eight different types of vitamins a day. It seems like a lot, but I've noticed a huge difference in my energy levels and alertness since I started taking them regularly about a year ago. I didn't get sick at all last winter while all of my friends and family where down and out for several days, so I must be doing something right... right?

To get the answer, I asked celebrity nutritionist JJ Virgin, author of The Virgin Diet, to reveal what vitamins every 20-something woman should take.

And, surprise! My extensive vitamin regimen isn't as crazy as my friend thinks.

Multi-Vitamin

Every woman should be taking a high-quality multi-vitamin to fill in the nutrient gap you miss in your diet, says Virgin.

"The big emphasis here would be on high-quality multi-vitamins since many store brands have poorly absorbable nutrients, nasty additives like corn starch and dyes, and in general the lowest amount of 'acceptable' nutrients rather than optimal amounts," Virgin tells Yahoo! Shine.

In other words, don't just buy the cheapest multi-vitamin at the store. Instead, ask your doctor for her recommendations.

Fish Oil

Studies show that fish oil improves everything from cognitive function to heart health. It's also shown to help keep your skin looking young.

"A study in the Journal of Lipid Research found the omega 3 eicosapentaenoic acid (EPA) in fish and fish oil could help prevent skin aging," Virgin says.

However, quality is key. "Many store-brand fish oils have been sitting on shelves for who knows how long and quickly become rancid (just like old fish does)," she adds.

Calcium

We all need to take calcium to keep our bones and teeth strong, but not just any calcium pill.

"Rather than take calcium alone, I would prefer getting it in a bone-support mineral that also includes magnesium, boron and other nutrients," Virgin says.

Magnesium

Magnesium is great for so many things, according to Virgin. The nutrient gives energy, helps muscle relaxation and relives constipation. Like calcium, the the form of magnesium you take is important.

"Choose a highly absorbable magnesium (such as magnesium citrate), since elemental magnesium (magnesium oxide) absorbs very poorly and can trigger diarrhea," she advises.

Vitamin D

Getting extra vitamin D through supplements is great idea because most people are low in this vital nutrient, according to Virgin.

"Keep in mind this will vary by climate," she adds. "If you live in Honolulu, your body might make sufficient vitamin D. If you live in Seattle, probably not."

Virgin recommends asking your doctor to administer a 25 hydroxyvitamin D test to check the vitamin D levels in your body. "You should be in the 60-100 ng/ml area," she says.

Vitamin B Complex

Lacking energy? Add vitamin B complex to your regimen, says Virgin.

"A B complex can help since many B vitamins assist in energy metabolism. Stress can also deplete B vitamins like crazy," she says. "It can't hurt: you simply excrete excess B vitamins in your urine."

Extra Supplements

A high-quality probiotic helps gut health, says Virgin.

"Also, if you're under a lot of stress or over 35, a digestive enzyme with HCl can help better break down food," she adds.

Tell us: What vitamins do you take to keep your body in tip-top shape?

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