When you’re taking zinc and magnesium together, it’s all about the dosages. The best supplement dosage for you depends on your individual needs–so make sure you’re discussing any new supplements with your own healthcare provider first–but there are some general guidelines.
While the two minerals work synergistically, research shows that taking too much zinc, or about 50 milligrams per day, can decrease the amount of magnesium you absorb and negatively affect magnesium balance. But that’s a hefty amount of zinc, exceeding the recommended upper limit of 40 milligrams per day.
For daily magnesium needs, the National Academies recommends that women consume 310 to 320 milligrams of magnesium each day, while men need 400 to 420 milligrams. Daily zinc needs are eight milligrams for women and 11 milligrams for men, respectively. The forms matter, too.
According to integrative physician Robert Rountree, M.D., magnesium becomes more bioavailable when it’s bound to certain organic compounds: “Magnesium absorbs water. So when you take straight-up magnesium, like magnesium oxide, it forms these clusters of water, and that basically hurries things along in the gut.” While this form may help digestion and regularity, it doesn’t do as much to increase serum levels of magnesium.
To boost absorption and really get the most out of your supplement, you’ll want to opt for a chelated form. “[Chelated] simply means the magnesium is bound to an organic compound that basically helps ferry it across the lining of the gut,” Rountree says. He recommends the gentle magnesium glycinate, and research agrees. A study that compared the different forms of magnesium found that magnesium glycinate has superior absorption versus inorganic magnesium oxide. Other forms like magnesium citrate, chloride, lactate, and aspartate are good and bioavailable options, too.
As for zinc? Ferira recommends (and takes) it in the chelated form of zinc bisglycinate, which she gets from mbg’s immune support+ supplement. Research shows that this specific form of zinc is about 43% more bioavailable than another common form, zinc gluconate.* Zinc bisglycinate has also been shown to beat out other forms (e.g., zinc picolinate and oxide) when it comes to absorption and improving your zinc status in the body.*