For a lot of people, coffee is the opening act of the day. Supplements come right after, usually swallowed together in one efficient, optimistic gulp. It looks productive. In some cases, it’s also a great way to cancel out what those supplements are supposed to do.
Roughly two-thirds of U.S. adults drink coffee every day, and nearly three-quarters take dietary supplements. That’s some serious overlap. Coffee changes how your body absorbs certain nutrients, which can shrink their payoff or push them out faster than you want.
Here are the supplements worth keeping away from your morning cup.
1. Iron
Iron doesn’t stand a chance against coffee. Coffee contains polyphenols, including chlorogenic acids, that bind to non-heme iron during digestion and reduce absorption.
“Iron is the most clearly affected by coffee,” Dr. Karan Rajan, chief science officer at Throne Science, told the New York Post. He added that this shows up most for people who menstruate, are pregnant, follow plant-based diets, or already run low on iron. Rajan suggests taking iron at least 1 to 2 hours away from coffee and pairing it with vitamin C to improve absorption.
2. Zinc
Zinc absorption can dip when taken with coffee, again because polyphenols bind minerals in the gut.
“Coffee can modestly reduce zinc absorption,” Rajan said, noting the effect depends on dose and timing. People supplementing for immune support or deficiency may get more out of zinc by separating it from caffeine.
3. Calcium
With calcium, the issue isn’t absorption. Caffeine increases how much calcium leaves the body through urine, with studies estimating roughly five milligrams lost per cup of coffee.
“For most people with adequate calcium intake, this is negligible,” Rajan said. If supplements are important for your bone health, spacing calcium away from coffee still makes sense.
4. Magnesium
Magnesium survives coffee better than most supplements, but caffeine still increases urine output, which can drain magnesium over time. Rajan suggested taking it later in the day.
There’s also a comfort issue. Magnesium citrate and sulfate already pull water into the gut. Adding coffee can turn that into cramps or a sprint to the bathroom.
5. B Vitamins
Most B vitamins hold up fine with coffee, but caffeine can increase urinary loss of some, particularly vitamin B1. Because B vitamins are water-soluble, excess amounts leave the body quickly. Rajan said this only becomes noticeable with high caffeine intake or low dietary B1.
Coffee isn’t the villain here. Timing is. Giving supplements a little space from your caffeine habit can be the difference between absorbing what you paid for and flushing it straight down the drain.
The post 5 Supplements You Shouldn’t Take With Coffee, Unless You Want to Waste Them appeared first on VICE.
