When it comes to taking vitamins and supplements, it turns out the ‘when’ is just as important as the ‘what.’ But, the good news is that nailing down the best time to take your vitamins isn’t rocket science either.

Arizona-based Naturopathic Physician Dr. Tricia Pingel, an expert on adrenal fatigue and the physical impact of stress on the body, confirms that “timing is critical.” To figure it out, she suggests you ask yourself: what is the purpose of the supplement in question.   

“Think about why you’re taking it. Supplements are, literally, meant to supplement your diet, so if it’s a nutrient you would normally get in food, it makes sense to take it with a meal. If it’s for energy or endurance, take it in the morning or close to a workout. If it’s for sleep, you should have it at night.”

Should I take vitamins with food or on an empty stomach?

A general rule of thumb is to take fat soluble vitamins—like fish oils—with a meal, Dr. Pinden advises.

Meanwhile, “Water soluble vitamins—B vitamins, magnesium, zinc, etc.—can cause stomach upset and some people can’t tolerate them on an empty stomach,” she notes, but adds that trial and error is the best way to determine what works for you.

Probiotics are also recommended to be consumed first thing in the morning on an empty stomach. Alternatively, Dr. Pinden suggests taking certain nutrient supplements before bedtime; a time when your body is resting, repairing itself, and “cleaning out the garbage.”   

What vitamins do I need to take?

Most commonly, Dr. Pinden sees people on a combination of B12 for energy, a multi-vitamin for general health, vitamin C for immune health, and fish oils for heart health. But you need to make sure the supplements you are taking are actually the right fit for your lifestyle and health needs.

You should be able to see the effects and benefits of any supplement you take. “There should be a tangible difference,” Dr. Pinden confirms. “The timeline can vary. Nutrients kick in pretty quickly, if you’re taking really good vitamins, so within a few weeks you should notice a difference.”

“It takes time to build muscle, so I’d say you need to give [anything for that goal] at least six weeks of regimented use. It may not be a 100% change, but you should see things go from, maybe, 20% to 30%. Adrenal supplements and hormone regulating ones take longer, more like one to three months. But it should be a linear trend of feeling a difference.”

Her trusty advice? Talk to your physician and educate yourself on what to look for on the label while you’re at it.

How to pick the best supplements on the market

Dr. Pinden says that you should always check the inactive ingredients on a label. “That list at the end shouldn’t be long. It should essentially be the capsule,” she said. “You should not be seeing a lot of stuff like palm oil, soy bean oil, maltodextrin, red number four, and so on.”

She continues: “On the label itself, not listed in the ingredients, it should say the form of the nutrient. For example, a lot of people are familiar with zinc, but zinc oxide is one form and zinc picolinate is another form. Zinc oxide, you don’t absorb, but zinc picolinate absorbs beautifully. Hopefully [consulting] a physician or reading up on it will point you in the right direction. B12 also has active and inactive forms. Ultimately, the label should be very clear. If you have to search, they’re hiding it!”

What should I avoid taking my vitamins with?

Dr. Pinden warns against taking vitamins or supplements with “anything else that goes into the liver.” In other words, most people should not take their vitamins with other medications—unless instructed otherwise.

“Tannins in black coffee, black tea, and wine, as well as alcohol, and drugs can block iron, which is one of our most common deficiencies, so it’s important to note not to take in conjunction with those,” she added.

When should I supplement with protein?

While whey-based products are often the go-to protein supplement for endurance athletes, Dr. Pinden said, once again, you have to look at the label. She also advises being wary of marketing ploys, like unfound claims that the powder is “muscle boosting” or “energy boosting.”

Personally, she tends to lean towards organic, clean, plant-based protein powders; which also avoids the inflammatory component from the dairy in whey. “It’s usually a better source and better made, with less junk,” she said. “But whey proteins do seem to be getting much better and more well made than they were five years ago.”

What supplements should I take before and after a workout?

While athletes can tend to lean towards powders, shakes, and bars to refuel, Dr. Pinden said that there’s no real replacement for food post-workout. And indeed, she’s a fan of food-based supplements over glucose gels. However, she has a rule of thumb to keep in mind when supplementing before and after an event.

“You’re trying to burn during a workout, so [opt] for any supplements that are aimed at burning energy and breaking down fat. Although I don’t think they’re always necessarily the healthiest,” she said. “I’m seeing a lot of people starting to add in [powdered] SuperGreens or SuperBeets, which I’m in favor of. Beets help dilate the blood vessels while running, so I’m seeing an uptake in that.”

“After a workout, it’s time for replenishing. Protein will help replenish the deficiency, and branched chain amino acids are popular for muscle building, but always try to replenish with food,” she said.