Can you also get too many vitamins?

Vitamins have a healthy image and for good reason. From resistance to energy supply, from blood to bones and from vision to muscles: vitamins are indispensable for the functioning of just about all parts of your body. They even take care of your skin from the inside out. And if you have a wound, there would be no scab without vitamins. So it’s no wonder that many people think: the more vitamins, the better. But as is often the case with everything that stands for ‘too’: you can also get too much of certain vitamins.

What do you finally need?

There are 13 vitamins that your body needs, but cannot make itself. So we have to get them through food. Not everyone needs the same amount of vitamins: the need varies from person to person. The Health Council has drawn up recommended daily allowances (RDAs) for different age groups, which cover the needs of 97.5 percent of people in that group. That means that the majority of people also have enough with less than the RDA. Only a small proportion (2.5 percent) need more than the RDA. A labeling RDA is used on the packaging of foods and supplements that is the same throughout Europe (see table). This can be seen as a kind of average RDA for adults. Children usually need a little less and the elderly and pregnant women sometimes need more.

Which vitamins should you watch out for?

Of the 13 vitamins, there are 6 where you have to be careful with high doses. Taking too much of these vitamins for a long time can be harmful to your health. These include vitamins A, D, E, B6, folic acid (B11) and niacin (B3). The European Food Safety Authority (EFSA) has set an upper limit for these vitamins; a maximum daily dose that is still safe for adults. You usually don’t get such high doses with your food. But that risk is there if you take them in high doses. These maximums are approximately between 4 and 50 times the RDA (see table below).

* in the form of nicotinamide, which is usually in supplements (there is another form: nicotinic acid, the safe upper limit of which is 10 mg per day)

How can you get too many vitamins?

You can almost only get an excess of vitamins if you take supplements that contain more than the RDA. We call this high-dose supplements. Or if you take more tablets than recommended on the package. Even if you combine different supplements, you run the risk of overdosing. For example, if you take a multivitamin (with all vitamins in it) with a separate vitamin D supplement or a vitamin B complex, the combined dose can exceed the safe upper limit. You can check this by adding up the dosages on the packaging and comparing it with the upper limits from the table. There is one exception and that is vitamin A. You can also get too much of this vitamin through your diet. This can happen if you eat liver often, because it can contain high doses of vitamin A. In short: if you want to take extra vitamins, it is wise to take a maximum of 1 x the RDA.

How do you know that you are taking in too many vitamins?

The symptoms of an overdose are different for each vitamin:

• With vitamin A, too much can cause headaches, nausea, dizziness, fatigue and abnormalities in the eyes, skin and bones.
• Too much folic acid (vitamin B11) in itself is not harmful to your body. The only drawback is that a possible deficiency of vitamin B12 can no longer be easily demonstrated.
• With vitamin B6, an overdose can affect the nervous system, with numbness, tingling and severe nerve pain in the hands and feet. This condition is also known as peripheral neuropathy.
• Bee vitamin D an overdose is associated with nausea, drowsiness, loss of appetite, constipation and harmful calcium deposits in the heart, kidneys and blood vessels.
• You usually do not notice an excess of vitamin E, but the excess accumulates in your body. This can disrupt processes in the tissues.
• With niacin (vitamin B3) it depends on which form you get too much. Most supplements contain nicotinamide. A very high dose of it can damage the liver and eyes. Sometimes supplements contain nicotinic acid. With too much of it, your blood vessels dilate and you notice that: it feels like a hot flash.

Are the other vitamins always safe?

No upper limit has been drawn up for the seven other vitamins (B1, B2, B5, B8, B12, C and K), because there are no known adverse effects at high doses. Only a high dose of more than 2,000 mg vitamin C (2500 percent of the RDA) cause intestinal complaints such as diarrhea. And people on blood thinners should be careful with doses greater than 100 mcg of vitamin K (133 percent of the RDI). This can reduce the effect of the blood thinners.

Better but not taking supplements at all?

You don’t have to go that far. As long as you stick to the recommended dosage on the package. It is also wise to ignore high-dose supplements and not to combine all kinds of supplements. It is good to ask yourself whether you really need a supplement. Vitamins are good for your health, but more is not always better. If you already get enough by eating a healthy diet, then a supplement will no longer have any additional effect. You only need some extras if you belong to a certain group. Even if you eat healthy.

When do I need extra vitamins?

Sometimes it may be necessary to use extra vitamins. The Nutrition Center and the Health Council recommend a daily supplement for certain groups. If you are not sure whether you need a supplement, contact your doctor or a dietician. They can advise you. A dietitian can also calculate for you whether you are getting enough vitamins with your diet.

The groups for which a supplement is advised:

• Vegans (people who don’t eat animal products): vitamin B12 (up to 2.5 mcg per day)
• Women over 50: vitamin D (10 mcg per day)
• Men over 70: vitamin D (20 mcg per day)
• Anyone with a dark (toned) skin tone: vitamin D (10 mcg per day)
• Anyone who doesn’t get out much during the day or covers their skin: vitamin D (10 mcg per day)
• Women who want to get pregnant or are just getting pregnant: folic acid (400 mcg to 10 weeks gestation)
• Pregnant Women: Vitamin D (10 mcg per day)
• Children up to 4 years: vitamin D (10 mcg per day)
• Breastfed Babies: Vitamin K (150 mcg per day up to 3 months)

In addition, according to the Nutrition Center, there are groups for which extra vitamins can be good, but for which there is no official advice. It’s about:

• Elderly who eat little (multivitamin)
• People who eat unilaterally (multivitamin)
• People following an extreme weight loss diet (multivitamin)
• Elderly people with stomach or intestinal infections (vitamin B12). Due to the infections, the absorption of vitamin B12 from the diet may be insufficient. Because vitamin B12 is well absorbed from a supplement, extra vitamin B12 can be useful for this group.
• When using drugs. Certain medicines can have a direct or indirect influence on your metabolism or the effect of vitamins with long-term use. In that case, ask your doctor or dietitian for advice.