Can You Get Too Many Nutritional vitamins?
Lots of people take vitamin dietary supplements simply to make it possible for they’re getting the advisable quantity of vitamins. (See additionally my episode on “Are Fruits and Greens Getting Much less Nutritious?”) However folks taking dietary supplements typically find yourself getting considerably greater than the advisable quantity of some vitamins, and extra is just not all the time higher.
Vitamin A: How A lot is Too A lot?
Vitamin A is an efficient instance. Vitamin A helps you see at midnight, combat off infections, and make pink blood cells. The advisable quantity is 3000 IU for wholesome grownup males and rather less for grownup ladies. However many vitamin dietary supplements—particularly high-potency formulations—can include as a lot as 5,000 IU.
When you take a few totally different dietary supplements, comparable to a multi-vitamin plus an immune-booster, you would simply go over the secure higher restrict of 10,000 IU. Indicators of vitamin A overload embrace complications, bone and joint ache, and itchy, peeling pores and skin. Ultimately, it may result in liver injury.
Vitamin A is just not onerous to get from meals. It’s present in eggs, milk, butter, and fortified breakfast cereals. Your physique additionally makes vitamin A from beta-carotene, which is present in, sure, carrots, however all types of different fruits and greens, as nicely. Beta-carotene is simply transformed into vitamin A as wanted, by the way in which, so dietary supplements or meals that include beta-carotene received’t contribute to vitamin A overload.
My recommendation is to examine the label on any and all dietary supplements that you simply take regularly and make it possible for the full quantity of pre-formed Vitamin A, or retinol, doesn’t exceed 2,500 IU per day.
Folic Acid: How A lot is Too A lot?
Folic acid helps you metabolize protein and synthesize DNA, protects towards most cancers and coronary heart illness, and prevents severe delivery defects. Though it’s necessary to get sufficient folic acid, extra is just not essentially higher. The primary drawback with getting an excessive amount of folic acid is that it may masks B12 deficiency—and it’s actually necessary to diagnose and proper B12 deficiencies as a result of they will result in neurological injury.
Not too long ago, there’s been some buzz about folic acid and colon most cancers. Suffice it to say that folic acid doesn’t trigger colon most cancers—the truth is, it protects towards it. But when you have already got colon most cancers, excessive doses of folic acid can feed tumor development, which is one other good cause to not go overboard with the dietary supplements.
You probably have any historical past of colon most cancers in your loved ones, you’ll wish to be notably cautious about dietary supplements; examine along with your physician.
Wholesome adults want about 400mcg a day and ladies want additional throughout being pregnant. Leafy greens like spinach and kale are a superb supply of folate, as are lentils and different legumes—and there’s actually no hazard of getting an excessive amount of folate from meals. The true concern is with dietary supplements. Now, should you’re pregnant, your physician has most likely given you a pre-natal vitamin that incorporates loads of folic acid. That’s as a result of it’s so necessary to make certain that you’re getting sufficient folic acid if you’re pregnant.
My recommendation for everybody else is to eat a number of folate-rich meals however to not get greater than 400 mcg of folic acid from dietary supplements. You probably have any historical past of colon most cancers in your loved ones, you’ll wish to be notably cautious about dietary supplements; examine along with your physician. And, in fact, everybody over 50 must be screened for colon most cancers yearly.