Medically reviewed by Allison Herries, RDN<\/p>\n
Drinking coffee with certain supplements is not necessarily harmful, but it can decrease how well your body absorbs them. This means that you may not get the full benefits from them.<\/p>\n
The good news is that you do not have to give up your morning coffee. Instead, timing your supplements appropriately can help your body absorb them more effectively.<\/p>\n
1. Iron<\/p>\n
Coffee contains plant compounds called polyphenols<\/a>. They\u2019re known for their antioxidant properties, but polyphenols also bind to iron, limiting the amount of iron your body can absorb.<\/p>\n According to some research, drinking coffee with an iron-rich meal<\/a> may decrease your iron absorption by about 35%.<\/p>\n A study from 2023 that looked specifically at the absorption of iron supplements taken with coffee, with or without breakfast, found that coffee decreased people\u2019s iron absorption by 54-66%.<\/p>\n This means taking iron with coffee won\u2019t give your iron levels the same boost as intended.<\/p>\n 2. Calcium<\/p>\n To get the most benefit from your calcium supplement<\/a>, it\u2019s important to avoid taking it with coffee so your body can absorb it.<\/p>\n The caffeine in coffee can interfere with your body\u2019s ability to absorb calcium from food or supplements. Coffee may also interact with vitamin D<\/a>, a nutrient that helps your body absorb calcium.<\/p>\n Coffee is also a diuretic, meaning it increases the amount of urine you make. Your body makes urine by filtering your blood. Some research suggests that coffee\u2019s diuretic effect filters calcium out of your body to be excreted or flushed out of your system through your urine.<\/p>\n 3. Vitamin D<\/p>\n Overall, research suggests that people who want to increase their vitamin D levels and get the most benefit may want to avoid taking vitamin D supplements<\/a> with coffee.<\/p>\n For example, some research suggests that caffeine can decrease how well vitamin D works. It does this by interfering with vitamin D receptors in your body.<\/p>\n Other research has found that people who take in more caffeine, such as those who drink a lot of coffee, have lower levels of vitamin D<\/a> in their blood. However, this research doesn\u2019t show that coffee or caffeine causes the deficiency\u2014just that there\u2019s an association.<\/p>\n 4. B Vitamins<\/p>\n Taking B vitamins<\/a> with coffee may prevent you from absorbing these nutrients as intended, or it may encourage your body to get rid of them.<\/p>\n This means you may not get the same benefits of taking them as you might otherwise. B vitamins include:<\/p>\n Some research has found that drinking coffee may decrease the levels of B vitamins in your blood. A study published in 2016 suggests that higher coffee intake is associated with lower thiamine levels<\/a>.<\/p>\n Research from 2018 suggests that caffeine may also interfere with folate, reducing levels in the blood.<\/p>\n B vitamins are also water-soluble, which means you may flush out the vitamins through your urine. Coffee can increase this effect by making you have to urinate more.<\/p>\n However, research is mixed. Another study notes that moderate coffee drinking, defined as one to two cups per day, is not associated with a significant change in vitamin B12 or folic acid.<\/p>\n 5. Magnesium<\/p>\n Coffee may influence levels of water-soluble magnesium supplements<\/a> in ways similar to how it decreases calcium and B vitamins: By increasing your urine volume, the mineral is filtered out of your body as you urinate more often.<\/p>\n In other words, taking magnesium with coffee means your body gets rid of the mineral more quickly, and you may not get the full effect. If you\u2019re taking a supplement for low magnesium levels, this may mean you\u2019re more likely to experience symptoms, like muscle cramping or fatigue.<\/p>\n 6. Zinc<\/p>\n Coffee and zinc<\/a> may not be a great combination. That\u2019s because drinking coffee may interfere with zinc\u2019s bioavailability, or the amount of your intake that enters circulation and is able to have an active effect in your body.<\/p>\n This may also be due to coffee\u2019s effect on vitamin D absorption<\/a>, as vitamin D helps you absorb zinc.<\/p>\n When Should You Drink Your Coffee?<\/p>\n When it comes to making the most of your supplements and avoiding interactions that decrease their effects, timing your coffee intake<\/a> may be key. Research suggests you may be in the clear if you drink your coffee 1-2 hours before taking your supplements or eating vitamin-rich foods.<\/p>\n Dietary supplements are minimally regulated by the FDA and may or may not be suitable for you. The effects of supplements vary from person to person and depend on many variables, including type, dosage, frequency of use, and interactions with current medications. Please speak with your healthcare provider or pharmacist before starting any supplements.<\/p>\n