Everything you need to know about Oats- from types and nutrients to anti-nutrients

February 9, 2021

Oats, scientifically known as Avena sativa, is a type of cereal grain present in the Poaceae grass family of plants. The grain refers specifically to the edible seeds of oat grass. Although it might be hated by some for its gooey texture upon cooking, oats are often prized for their nutritional value, health benefits and the various ways of preparation. Oats are edible seeds of the plant, of which the hulls or husks are removed and hence called as the oat groats/ kernel. The different varieties of oats start out as oat kernels and vary in the extent of processing techniques and somewhat in their nutrient profiling too. Oats can be modified and consumed in the following ways:

Oatmeal- Oatmeal is a type of coarse flour made of hulled oat groats and consequently a meal made using the same.

Overnight oats- This is a quick, easy no-cook solution of eating oats. All you have to do is Add sufficient amounts of water for oats to soak overnight without fully absorbing all of the liquid and draining the remaining liquid and rinsing the oats before eating.

Oat flour- These are oats that have been ground to a flour-like consistency.

There are different types of oats which you can see on the supermarket shelves, viz.,

  • Steel cut or Irish oats

Steel cut oats are somewhat similar to the unprocessed oat groats. Whole oat kernels are turned into pieces using large steel blades. These oats have a coarser, chewier texture and nuttier flavor than rolled or quick oats and also take longer to prepare (15-30 minutes).

  • Scottish oats

Scottish oats are those that have been stone-ground into a meal, creating a porridge-like texture when cooked. Stoneground flour is whole grain flour produced by the traditional process of grinding grain between two millstones.

  • Rolled or old-fashioned oats 

Rolled oats are formed when whole oat groats are steamed, rolled and flattened into flakes, and then dried to remove moisture. These techniques make rolled oats shelf-stable. They have a milder flavor and softer texture and take 2–5 minutes to prepare.

  • Quick or instant oats

Quick oats or instant oats are those that are even more processed than the latter two. These are partially cooked by steaming and then rolled even thinner than rolled oats. They cook very quickly and have a mild flavor and a soft, mushy texture.

Nutritionally, oats are packed with Beta-glucan, a soluble fiber component which is generally the major contributor for its weight loss claims. Whole grain oats contain a considerable amount of valuable nutrients such as proteins, carbohydrates and micronutrients such as vitamin E, folate, zinc, iron, selenium, copper, manganese, carotenoids, betaine and choline. 

Whilst it has a good nutrient profile and can be considered as ‘fit for health’, it has a high glycemic index. It simply means that your blood sugar levels spike up immediately after its consumption.

Moreover, the most important factor to be considered is the antinutrient content. Oats contain phytic acid which interferes with nutrient absorption and causes gastric disturbances (bloating, gas). However, the amount of this antinutrient can be lowered by soaking oats and discarding the water before eating.

The best way to reduce phytic acid in oats is by opting for overnight oats or soaking the oats with a dash of acid- apple cider vinegar or lemon juice to the soaking liquid and you will have a delicious batch of no-cook oatmeal that is ready to eat.

Oats are also found to produce a series of phytochemicals (compounds produced by plants for their protection) which are Saponins(1). Saponins are naturally produced as foam-producing compounds by many plants. Due to the bitterness, throat-irritating and inhibitory activity of saponins, they are considered to be ‘antinutrients’. However, greatest amounts of saponins are lost during soaking in salt water followed by pressure cooking. (Read more about Saponins: https://www.thrivefnc.com/blog/plant-antinutrients-saponins/)

Flavone-C-glycosides are yet another plant defense mechanism which is present in abundant quantities in the oat plants (2). These defense mechanisms basically work to deter larger animals for which some plants have sharp spines or thorns, while others have leaves that sting or are bitter to taste.

Owing to their supposed nutritional value, oat-based food products like breads, biscuits, cookies, probiotic drinks, breakfast cereals, flakes and infant food are gaining increasing consideration. These preparations also contain additives, binders, preservatives, and other chemicals which almost destroy the various benefits associated with consuming oats.

If oats have topped your favourites’ list or you are someone who wants to give them a try then eat them in their plain and natural form, do look for gluten free oats and always soak them overnight and discard the water so that you aren’t consuming any antinutrients. 


  1. https://digital.library.adelaide.edu.au/dspace/bitstream/2440/56814/2/02whole.pdf
  2. https://www.healthline.com/nutrition/rolled-vs-steel-cut-oats#definitions
  3. https://www.hsph.harvard.edu/nutritionsource/food-features/oats/
  4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4325078/ 
Ria Jain
Functional Nutritionist

Ria has a Master’s in Nutrition and Dietetics and is in a permanent research mode and keeps the rest of us at iThrive (Previously ThriveFNC) updated with her latest findings in the field of Nutrition. Her articles on iThrive's blog are an expression of her research findings. We really don’t know what we’d do without her support and her focus.

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