Are you timing your supplements right?

Finding quality supplements can be a time consuming feat – analysing labels on supplement bottles and researching the difference between magnesium citrate and magnesium glycinate.
But if you’ve started your regimen, and you’re not seeing the results you were hoping for, timing could be the cause.

Mis-timing your supplements can dramatically decrease their absorption, and in some instances, cause additional symptoms like nausea or sleeplessness.

Follow this practitioner-approved guide for a rough outline on what to take and when, while avoiding unwanted side-effects from supplements. That said, your supplement needs are unique. For a regime that’s tailor-made for you, you should book an appointment with one of our naturopaths.

Breakfast supplements

“Vitamins and minerals should always be taken after eating food. While taking them on an empty stomach may increase absorption, it’s not worth the gastric issues like stomach pain and nausea that clients experience. Food buffers the stomach’s acidity, and protects the gut lining from irritation,” says Naturopathic Doctor Benita Perch.

 “The exception to this rule is when taking herbs, which can be consumed on an empty stomach. Energising adaptogens like rhodiola, lion’s mane mushroom, cordyceps and gingseng should be taken in the morning to support your energy throughout the day,” she adds.

Studies suggest that taking probiotics during or after a meal is most effective, as food helps buffer the acidity of the stomach, ensuring the survival of good bacteria. Your stomach acid is least acidic in the morning when you wake up, and most acidic after a heavy meal, whilst lying down and during the night, specifically between the hours of 10pm and 2am. So, during, or after breakfast is optimal.

High quality formulas which use modern technology to protect probiotics help ensure good bacteria survive the acidity of the gut. Look out for specialised capsules, strains which are resistant to stomach acid or formulas which use microencapsulation.

B vitamins and vitamin C support energy production and metabolism, so should be taken in the morning. If consumed late at night, they can cause sleeplessness.

Multivitamins and prenatals usually contain B vitamins and vitamin C, so should be taken in the morning. They also contain fat-soluble nutrients like vitamins A, D, E and K which need a source of dietary fat to be absorbed well. 

Nutrients that need a healthy source of fat

Breakfast choices like eggs, avocado or yoghurt offer a good pairing to boost bioavailability of fat-soluble nutrients. Other options include olive oil, nuts, and fatty fish.

One study showed that when people took vitamin D alongside a source of dietary fat, they had 32% more vitamin D circulating in their blood 12 hours later than those who took the same dose without fat.

Fish oil comes in three formats: triglycerides, which are more readily absorbed and ethyl esters, which are synthetic and less bioavailable. When taken alongside a high fat meal, one study has shown that the absorption rate of ethyl esters improves threefold, and the absorption of triglycerides increases from 69% to 90%.

A single serving of a multivitamin or fish oil may recommend more than one capsule a day. Splitting the dose of your multivitamin or fish oil allows more time for your body to absorb the nutrient, improving bioavailability. 

“The reality is that splitting your dose isn’t always achievable. Often people find it tricky to remember to take their second dose, so while split-dosing multivitamins or fish oil offers better bioavailability, I would rather my client remember to take the full dose and take it in one sitting,” says Benita. 

CoQ10, a powerful antioxidant, is also a fat soluble nutrient. Similarly to B vitamins, it helps support energy production, so should be taken after breakfast or lunch.

Sensitive nutrients

Iron is a sensitive nutrient, and should be isolated from minerals, multivitamins, most kinds of food and drinks like tea or coffee. You should wait 2 hours either side of taking iron before consuming anything else. 

Other minerals and compounds like tannins and polyphenols (which tea and coffee are rich in) can reduce its absorption rate. In fact, tea inhibits iron absorption by more than 85%. Nuts, fruits and grains are rich in iron-inhibiting compounds and minerals. “I recommend taking your iron supplement after lunch, as this allows sufficient space from any other minerals you might be taking, or foods that inhibit iron,” says Benita. 

If you’re feeling peckish around the time you take your iron supplement, pair it with an orange, as vitamin C helps increase iron absorption. Probiotics can also help boost the absorption of iron - but avoid probiotic yoghurts, which contain calcium - another iron-inhibitor.

How frequently to take iron is dependent on the individual. For those who have very low iron stores, it may be more beneficial to take iron daily, but for others, it may be best to take iron once every other day. Some studies suggest that taking iron daily can increase hepcidin production, which inhibits iron absorption. 

Zinc is best taken after eating - food helps buffer the gastric symptoms like nausea which occur as a side effect of this mineral. Take it at least two hours before or after taking other mineral formulas, which can interfere with absorption.  Zinc can be taken at any time of day as it doesn’t affect sleep. 

Supplements you should take before bed

Known for its calming properties, magnesium can be taken before bedtime to support better sleep. However, magnesium doesn’t cause drowsiness, so can be taken in the morning as well as evening. Consistency is key with magnesium supplementation – so prioritise taking it at a time you can maintain every day.

If you take a calcium supplement, it should be in a combined formula with magnesium, or taken alongside it. Alone, calcium can cause cardiovascular problems, but when paired with magnesium, it provides benefits. Pair calcium with food, as stomach acid supports its absorption. Or, take calcium before bedtime, when stomach acidity is higher. Calcium citrate is an outlier and absorbed well regardless of whether it is eaten alongside food.

Soothing adaptogens like reishi, ashwagandha and valerian support sleep and relaxation. These can induce a feeling of sleepiness, so are best taken when you’re ready to drift off.

In summary

Core supplements like probiotics, multivitamins, fish oils and magnesium should be taken daily, as consistency yields the most optimal results. 

At IMI we recommend working with a naturopath before you start a new vitamin or mineral outside of your foundational daily multivitamin – we’ll use testing to confirm whether it’s necessary or helpful that you add it to your routine.

Our naturopaths track your progress as you go, and can help you find the cause of any new symptoms that may arise, making recommendations or tweaking your regimen to your needs.

We check your levels a final time to ensure your nutritional profile is replenished before taking you off a supplement.

References
N U Stoffel et al, Iron absorption from supplements is greater with alternate day than with consecutive day dosing in iron-deficiency anemic women, 2020.
T A Tompkins et al, The impact of meals on a probiotic during transit through a model of the human upper gastrointestinal tract, 2011.
P Treven et al, The effect of food matric taken with probiotics on the survival of commercial probiotics in simulation of gastrointestinal digestion, 2024.
B Dawson-Hughes et al, Dietary fat increases vitamin D-3 absorption, 2014.
L D Lawson, B G Hughes, Absorption of eicosapentaenoic acid and docosahexaenoic acid from fish oil triacylglycerols or fish oil ethyl esters co-ingested with a high fat meal, 1988.
Seeking Health, The Pulse Method, 2018.
Z Zakrewska et al, Prebiotics, probiotics and postbiotics in the prevention and treatment of anemia, 2022.
A Apte et al, Effect of probiotic and prebiotics supplementation on hemoglobin levels and iron absorption among women of reproductive age and children: a systematic review and meta-analysis, 2025.
Y Wang et al, Probiotics and prebiotics as dietary supplements for the adjunctive treatment of type 2 diabetes, 2023.