When Is The Best Time To Take Vitamins? A Scannable Guide

Stomach aches, nausea, and fatigue are a few of the side effects you might feel after taking your vitamins. However, taking your supplements at the right time of day or night can help combat these side effects for good.

“Vitamin A is a fat-soluble vitamin. Like all fat-soluble vitamins (A, D, E, and K), its bioavailability increases when they are taken with a source of fat,” explains registered dietician Maya Feller, R.D., CDN.

Either take your vitamin A with a full meal containing healthy fats or make a snack with ingredients like avocado, peanut butter, etc. to ensure it's absorbed properly. 

“Vitamin C is a water-soluble vitamin and does not need to be taken with food to increase bioavailability,” Feller says.

However, when taken in excess, some people experience GI symptoms including upset stomach and loose stools when taking vitamin C, so keep that in mind if you’re trying a new product. 

Anyone who is prone to specific types of kidney stones will want to talk to their doctor first.

Vitamin D's bioavailability increases when you take it with a meal that contains fat, Feller says. However, the time of day doesn't matter as much.

While consuming too much vitamin D is really not a concern for the average person, it's best to partner with your health care provider to be sure.

Vitamin E is another fat-soluble vitamin that should be taken with a meal that contains healthy fats to increase absorption.

Vitamin K is a fat-soluble vitamin that's best taken with food.

“B vitamins are water soluble, so [they] can be taken on an empty stomach any time of the day,” Desai says. 

However, she adds that some people do report difficulty sleeping after taking some B vitamins, so she recommends taking them in the morning to be safe. 

Because most multivitamins contain B vitamins, Desai recommends taking them in the morning to avoid sleep disruptions.

Since multivitamins also usually include some or all of the fat-soluble vitamins (A, D, E, and K), you'll want to take them with food as well. 

For optimal absorption, Desai recommends taking prenatal vitamins with food. “Many women experience nausea during pregnancy, and taking a prenatal vitamin with food lowers the chance of nausea, acid reflux, and upset stomach,” she adds. 

“Iron is a mineral that can be taken with a source of vitamin C to increase its absorption,” Feller says. Iron vitamins can be taken on an empty stomach, but its best to take with food.

This mineral can cause stomach discomfort in those prone to GI concerns, she says. If this happens to you, consider pairing your supplement with food (but avoid high doses of calcium, fiber-rich foods, or taking alongside thyroid medications to prevent possible interactions).

Feller points out that those with heart, kidney, or gastrointestinal considerations and those on prescription medications should check with their doctor before starting a high dose magnesium supplement.

Calcium is another nuanced supplement when it comes to its relationship with other medications (particularly thyroid medicine), so make sure to check with your physician before buying it and consider the optimal time of day to supplement to avoid absorption barriers or side effects.  

“Additionally, people with documented low blood pressure may not want to take calcium supplements as it can decrease blood pressure1,” Feller says. 

Different probiotics contain different types of bacterial strains, so their effects vary greatly. For this reason, Feller explains that there is no universal recommendation for when to take probiotic supplements. Look to the label to see whether or not yours should be taken with food, in the morning, etc. 

Protein powder supplements are often taken with food. You can easily blend them into a shake or mix them into yogurt, but you can take protein powder with just water if needed, too. 

As for timing, that really depends on your goal and daily schedule. If you plan on working out that day, consider taking protein within a few hours before or after your workout.

The protocol for collagen greatly varies depending on the forms included in your supplement, Desai says. However, most of them should be taken with food to increase absorption, she notes. Given that many collagen supplements come in powder form, it’s easy to work them into smoothies, lattes, yogurt, etc. 

There’s certainly no harm in taking collagen supplements in the morning, however, emerging research suggests2 that taking collagen peptides before bed may help limit awakenings at night. 

Considering hemp-derived CBD has a calming effect, it’s particularly beneficial to take before bed or when you want to feel relaxed. 

Research shows that the absorption of CBD may be slightly increased when taken with high-fat foods3, though you don't necessarily need to take yours with a meal.

This supplement doesn’t come with quite as many contraindications, but it’s always best to consult your physician before adding CBD into your regimen. 

Taking vitamins and supplements can be a valuable way to fill gaps in your diet and give your body the nutrients it needs to thrive.

Some vitamins and minerals work best when taken in the morning, while others are well-suited for nighttime. You'll also want to take certain supplements with food in order to increase their bioavailability (and decrease your risk of digestive upset).

Also, remember to double-check your supplement routine to ensure you're not consuming more than the recommended dose, as many vitamins and minerals have a tolerable upper limit (UL) or max daily intake that has been demonstrated to be safe.

This guide provides a general primer on when to take your vitamins and supplements, but refer to the label on your particular product to know for sure.