Do you know your RDAs?


On any trip to the supermarket, if you read the food labels on the products you buy, you are going to come across the term Recommended Daily Allowance or RDA. The RDA for each nutritious element in a food item is assigned a number and tells you how much of a vitamin or mineral is in the item and by what percentage it contributes to the amount of that vitamin or mineral you should be having daily.

The RDA is a guide to let you know the amounts of a vitamin or mineral you need to consume to keep you healthy and well-nourished. 

You can view example RDAs here

Too much of a good thing

Most often the case is we need to be eating more of a particular vitamin or mineral, especially if the majority of food eaten is processed. However, there is another number we should be aware of and that is the TUL (Tolerable Upper Limit). This is the maximum amount of each vitamin and mineral that you can safely take without overdosing. (Yes, you can overdose on food and even water!)

Do note that, usually, ou can safely go over the RDA of a vitamin or mineral without any adverse side effects or risk of overdose as long as you don’t hit the TUL. You can often take a dose much higher than the RDA without coming anywhere near to the UL amount. For example, you can take 50 times the RDA of Vitamin B6 before hitting the TUL. 

Take care with supplements

It’s often assumed that supplements are healthy as they give us convenient access to good doses of vitamins and minerals we may otherwise be missing in our diet. However, they come in concentrated forms so you need to take care not to overdose. Supplements shouldn’t be used as a replacement for natural food. You should try to get as many of the nutrients you need to make up your RDA from your daily diet.  

Be aware also that some supplements are riskier than others as the TUL is close to the RDA so it’s easy to overdose on them. Some of these nutrients, such as Vitamins A, K and E can build up in the body and become toxic overtime. Minerals such as iron and selenium can also cause problems in too high a dose as they are retained in the body.

Check with your doctor before taking supplements if you have a health condition. They may interfere with existing medication you are taking or produce unwanted side effects.