Growing up as a celiac on a gluten-free diet, when I asked "Are oats gluten free?" I was told definitely not!
However that way of thinking has been challenged in recent years.
Nowadays there are a number of companies who produce gluten-free oats that are supposed to be safe for those of us on the gluten-free diet.
Oats do not actually contain gluten, but a similar protein, avenin, which can cause problems for those who are gluten intolerant. However, it seems that this is not the main reason for excluding them, and that the process of growing and harvesting is to blame.
Normally, wherever oats are grown it is likely that other cereal crops such as wheat, are growing in the same field.
When the crop is harvested it is almost impossible to prevent contamination, both at the harvesting stage and transportation to the mill. Add to this the fact that oats are normally processed in facilities that also deal with wheat products and the contamination risk increases.
Some manufacturers are now producing gluten-free oats which have been processed on dedicated lines.
These are sold as suitable for the gluten-free diet. They are normally labelled as pure or certified gluten free oats. Be aware, however, that they are more expensive to produce and therefore you are unlikely to find them as an ingredient in commercial products.
There is a difference of opinion as to whether certified gluten free oats are really safe for coeliac sufferers to eat.
I can say that I have tried them, and suffered no ill effects, even though I am very sensitive.
It may be worth asking your doctor or dietician for advice as to whether to include them in your diet if you are gluten intolerant.
Here in the UK, if you direct the question - are oats gluten-free - to the Coeliac Society, they will err on the side of caution, but it really is a personal choice.
You might like to remember the saying "when in doubt, do without" before making your decision.
If you're not happy eating them there are alternatives. You can make porridge, for example, from millet flakes, or buckwheat. These, along with Rice flakes, can also be used in muesli mixes.
I have included some recipes on this site where you can use either oats or millet flakes.