Looking after your teeth is an important part of your everyday life. Healthy teeth look and feel better and good oral hygiene is good for overall health. There are some things you should be eating in order to have healthy teeth – here are some of them: Calcium. This is needed for healthy, strong teeth. You may begin to get cavities and decay if you do not have enough in your diet. Children need more calcium as they grow. Iron. You may notice sores in your mouth – this can be a sign of iron deficiency. Vitamin D. This is important because it helps you absorb calcium. Signs of a deficiency can include a burning sensation in the mouth, a dry mouth or an unusual metallic taste. B3. Bad breath can be a sign that you’re not consuming enough B3 vitamin. Vitamin C. Whilst this is usually associated with the immune system, a lack of it in your diet can also cause your teeth to loosen and your gums to bleed.