I used to take my multivitamins with my morning cuppa coffee though I knew that there were side effects of doing so.  But I wanted to get over and done with popping all my vitamins first thing in the morning before I got busy and forget all about it later. The last straw for me was when I popped my calcium, super lutein, fish oil and iron with a mug of coffee. Minutes later, I felt a gagging feeling in my throat. My tummy felt bloated. I felt nauseous and bloated for the next few weeks. That was the last time I popped my vitamins with my coffee.

These days, I space out my mug of morning coffee and green tea with vitamins popping over several hours. The bloatedness and stomach discomfort are gone.

A cup of coffee and a daily multivitamin go hand-in-hand — they’re just part of your morning routine. While taking a multivitamin and drinking a cup of coffee isn’t generally dangerous, you might not be getting all of the nutrients your supplement has to offer.  Any beverage or food containing caffeine such as coffee, tea, chocolate and some sodas can inhibit the absorption of vitamins and minerals and increase their excretion from the body.  You’re better off waiting until after you finish that cup of joe.

Doubling Up on Caffeine
Some multivitamin supplements already contain caffeine. So if you enjoy a steamy cup right after taking your multivitamin, you’re getting way more caffeine than you may realize. The excessive amount of caffeine in your system can make your heart start racing and leave you jittery. If the label on your multivitamin has wording like “mental alertness” or “energy,” the vitamin pill likely contains caffeine.

Nutrients Cruising Through Your System With Caffeine
Coffee is a stimulant, so it revs up the gastrointestinal tract and makes things move more quickly through your body. You won’t absorb all of the nutrients from a capsule that is cruising through your system. The good news is you don’t have to skip your morning mug. Just drink your coffee first and then wait 10-15 minutes or longer before you pop your vitamins with a glass of water.

Water-soluble Vitamins & Caffeine
When it comes to water-soluble vitamins, caffeine reduces the amount of nutrients available to the body. Water-soluble vitamins like Vitamin C are normally excreted in the urine when there is an excess amount. Since coffee is a mild diuretic, it causes more urine to be produced. As more urine is released by the body, it takes Vitamin C and the B vitamins with it. In addition, caffeine directly interferes with how the body can metabolize B vitamins. As a result of this diuretic action, individuals who drink coffee can become depleted of Vitamin C.

Calcium
Caffeine causes calcium to be excreted in the urine and feces. For every 150 mg of caffeine ingested, about the amount in one cup of coffee, 5 mg of calcium is lost. This effect occurs even hours after the consumption of caffeine. One study of postmenopausal women found that those who consumed more than 300 mg of caffeine lost more bone in the spine than women who consumed less.

Caffeine also inhibits the amount of calcium that is absorbed through the intestinal tract and depletes the amount retained by the bones. Studies have shown that women with high caffeine intake suffer more hip fractures than those who avoid caffeine or drink in moderation (1 to 2 cups per day).

Vitamin D
Caffeine inhibits vitamin D receptors, which limit the amount that will be absorbed. Because vitamin D is important in the absorption and use of calcium in building bone, this could also decrease bone mineral density, resulting in an increased risk for osteoporosis.

Iron
Caffeine interferes with the body’s absorption of iron, which is necessary for red blood cell production. Drinking caffeine at the same time as an iron source can reduce absorption by up to 80%, according to the Nutrition Desk Reference. Any beverage containing caffeine should be separated from iron-containing foods or supplements by at least one hour.

Other Vitamins and Minerals
Caffeine may reduce the absorption of manganese, zinc and copper. It also increases the excretion of the minerals magnesium, potassium, sodium and phosphate. There is also evidence that caffeine interferes with the action of vitamin A.