To get the most out of your supplements, it is important to take them at the right time and in the right conditions. But this is easier said than done.

Which supplements should be taken with food, and which are best taken on an empty stomach? Which supplements pair well together, and which do not? Use this guide as a reference to help you develop your schedule to ensure maximum effectiveness.

Fat-soluble vitamins such as A, D, E, K, are needed to maintain good health, and are better absorbed with a balanced meal that includes protein and fat. According to a study in the Journal of the Academy of Nutrition and Dietetics, vitamin D3 is 32% better absorbed when taken with a meal containing some type of fats such as cheese, dairy, nuts, or avocados. To learn more about vitamin D specifically, read “What You Need to Know about Vitamin D!”

The body uses fat-soluble vitamins in small amounts and stores any excess vitamins in the liver and fatty tissue. This is why they are called “fat soluble.” Excess amounts can have detrimental results, so they are not recommended to be taken in doses exceeding the manufacturers or your health care practitioner’s recommendation.

Water-Soluble Vitamins

Water-soluble vitamins such as B and C, are not naturally produced or stored within the body. Thus, individuals need to get these on a frequent basis from either a healthy diet with animal- or plant-based sources or from supplementation.

Since B vitamins are water-soluble and only so much can be absorbed at any given time, take these throughout the day. They are also best taken on an empty stomach because an acidic environment helps improve absorption. The Linus Pauling Institute at Oregon State University has shown an inability to absorb vitamin B12, resulting in a B12 deficiency, is often caused by low levels of stomach acid and digestive enzymes.

Don’t get carried away, though — many “energy drinks” contain B vitamin supplementation that, in excess, leads to B vitamin toxicity.

Vitamin C

Like vitamin B, vitamin C is water-soluble and best taken in divided doses throughout the day to help with absorption. Many people think that “mega” doses of vitamin C are good when you have a cold, but it’s mostly just inefficient. Excess vitamin C is not absorbed, and can be seen being flushed out in a deeper-yellow urine. Smaller doses throughout the day can help keep blood vitamin C levels elevated and minimize any possibility of upset stomach.

If stomach sensitivity is an issue, taking a buffered form of vitamin C (such as Buffered Vitamin C by Integrative Therapeutics) can help – especially when taking doses larger than 1,000 milligrams. Keep in mind that vitamin C, or foods rich in vitamin C, have been shown to enhance the absorption of iron.

Iron and probiotics

Taking iron in the morning is the best time for most people. According to the National Institutes of Health, iron should be taken on an empty stomach. Iron is best absorbed in an acidic environment, and the stomach becomes considerably less acidic when full.

Optimal probiotic use is ensuring that the good bacteria make it to the gastrointestinal tract without being destroyed first. Research from Beneficial Microbes suggests probiotics should be taken either with or just prior to a meal containing some fats. This increases the probiotic’s chances of survival against harmful, destructive stomach acid as it travels through the body.

It is ideal to use one with acid-resistant capsules, pH-targeted release, and a high bacteria count — such as UltraFlora Spectrum or UltraFlora IB.

Oils (fish, borage, flax, etc.) and Protein

Oils should be taken with food and at least one hour away from exercise and at least one hour before bedtime. This is because high levels of activity and lying in a prone position are known to generally interfere with digestion. Since oils are food substances, there is no reason to think that digesting oils is any different. If you have had trouble digesting fish oils previously, consider a fish oil that contains lipase such as OmegAvail Ultra by Designs for Health.

Although the ideal timing for protein has been debated for a long time, a study from Strength and Conditioning Journal observed that taking protein (and/or amino acids) immediately following resistance training is more effective in increasing muscle growth than if one waits to take protein until later.

Calcium and fiber

According to the Mayo Clinic, calcium citrate can be taken with or without food since it is very bioavailable. Other calcium products, like ones containing calcium carbonate, should be taken with food. Calcium is best absorbed in smaller doses; once in the morning and once in the evening. Adding vitamin D will help your body absorb calcium more efficiently, which is why milk has been fortified with vitamin D since the 1930s. Just as important as what to take with calcium is what to avoid taking with it: magnesium, zinc, and iron.

With fiber, you should take some throughout the day at each snack and meal. Otherwise, it can worsen the kinds of digestive problems most fiber users are trying to improve. I typically recommend Herbal Bulk by Genestra for those looking for a great fiber supplement.

Mood-boosters and relaxers

Mood-boosting and relaxing supplements like 5-HTP, St. John’s wort, valerian, and melatonin are each taken for slightly different purposes. But whether you are taking one as an antidepressant, for weight loss, or as a sleep aid, all have a reputation for being sedating. While some people can take them whenever without feeling drowsy, most are better off incorporating them into their before-bed routine.

How long it is taken before bed depends on the supplement. For instance, melatonin should be used well before bed when travelling east to help adjust your internal clock and beat jetlag. A supplement like valerian can simply be taken an hour before bed or even right before turning off the lights. You can learn more about how to use the most common mood-boosters and relaxers for sleep purposes by reading “Which Sleep Aid is Best for You?“

What is the alternative?

By this point, you may be asking “what happens if I just take everything I need at once for convenience?” In most cases, it is likely not harmful to do so. It is a trade for a little less absorption (or bioavailability) for a little more convenience. The one-a-day multivitamin is a good example of this concept. But if you can make time to take each of your supplements in the ideal manner, you will likely find them to be more effective. Finding the right balance for your lifestyle and needs is the key.

This newsletter should help you get the most of your supplement regimen and will hopefully lead to optimal results.

If you have any questions regarding the concepts discussed here or anything else, please feel free to fill out our Ask the Doctor form found at the Doctors Corner.

Yours in health,

Dr. Gregg Gittins