Calcium is great for your bones and that is one reason why it's so important to make sure that you get a lot of it. In fact without calcium you can end up suffering from osteoporosis and other conditions. At the same time calcium can also help with many other things – and for instance it can help you to improve the strength of your contractions, improve your blood pressure, help the brain carry messages, clot the blood after injury, prevent heart attack and premenstrual syndrome and colon cancer.
However despite all of these important benefits of calcium there is still such thing as getting too much of a good thing and if you overdose on calcium or just get generally too much of it in your diet, then you can suffer effects that are just as bad as if you didn't get enough calcium. Here we will look at what too much calcium can do to your health and we will look at how to avoid overdosing.
How Much Calcium Do You Need?
Most people don't need to worry about having too much calcium. In fact for most of us the problem is the opposite – that we don't get enough calcium. This is why many people are recommended to take a multi-vitamin and mineral supplement that includes calcium.
As a rule the maximum amount of calcium you can safely consume is 2,500 milligrams of calcium – and that's a lot. In reality though you don't need anywhere near this much. For most health adults all you will need is around 1,000 milligrams of calcium a day. Adults over the age of fifty can also benefit from increasing this to 1,200 milligrams which will protect them from deteriorating bones to some degree. You might also want to take some more calcium if you are going through your menstrual cycle. Of course children also need less calcium than adults and newborns should have around 210 milligrams, up to 270 for seven months and 500 milligrams up to eight years. Between 9-18 it's a good idea to give children a slightly higher dose than adults though – around 1,300 milligrams – as they will be growing new teeth and bones. Remember 2,500 won't cause any harm, so it's fine to go this high.
Interestingly it's also a good idea to supplement your calcium supplement with magnesium. This is because magnesium transports calcium to your cells. Aim to eat at least half the amount of magnesium as you do calcium; so for most healthy adults that's around 500 milligrams of magnesium.
Side Effects of Too Much Calcium
So what are the actual effects of too much calcium? Well the acute symptoms of calcium overdose can cause nausea and vomiting, muscle weakness, diarrhea or constipation and drowsiness.
Too much calcium over time can cause an irregular heart beat and can lower blood pressure. In serious cases too much calcium can be damaging to the brain (and this is why calcium binding proteins are believed to be good for cognitive function). This can then result in confusion, fits and loss of consciousness. A build up of calcium in the blood is called 'calcification' and when this builds up too much it can cause cardiovascular diseases.
Ironically while many people take extra calcium to improve their bone health, this can also block the uptake of manganese and that is actually bad for bone health. Meanwhile many people report that taking too much calcium can cause joint pain. Finally, excessive consumption of supplementary calcium can increase the likelihood of kidney stones. These stones are often made up of excess calcium oxalate, and the RDI for calcium is actually based on the likelihood of developing kidney stones.
The risk of calcium causing joint pain or kidney stones is increased with the simultaneous consumption of vitamin D. In one study women who consumed 1,000 milligrams of additional calcium and 400 international units of vitamin D for 7 years were found to have a 17% higher chance of developing kidney stones.
Interestingly though studies also found that getting the same amount of calcium naturally as part of a balanced diet was less likely to cause kidney stones – suggesting that it's important to get your calcium naturally.