Is Oatmeal Always a Healthy Choice?
Dr. LAM Soe Tjhoen
Resident Medical Officer
Oatmeal has long been marketed as a healthy food. Is it the whole truth?
While all called “oatmeal” or “breakfast cereals” in Chinese, cereal, oatmeal, muesli and granola are different in ingredients and nutrients. In Hong Kong, cereal flakes, oatmeal, granola and muesli (or oat original) are the four major types of breakfast cereals.
As the most common breakfast option, cereal flakes are made with molded grain (mostly maize or wheat) powder. Products like cornflakes tend to appeal to children with cute shapes and rich flavours, which have to do with the addition of powdered sugar, food colouring, seasonings, etc.
In Hong Kong, most major brands have their own lines of oatmeal products. Oatmeal is mostly consumed as porridge added with other cereals/fruits or mixed with rice. Marketed as “instant”, “quick cooking” or “whole rolled oats”, most oatmeal products have been steam-cooked, baked, sliced and processed during the manufacturing process. While processed oatmeal is safe to eat when uncooked, most people find it too firm and dry for raw consumption.
Compared with cornflakes, granola looks more like the original cereals and retains the most nutrients. Mixed with nuts and dried fruit, granola is baked with honey until golden-brown and crisp.
Muesli is prepared with crushed cereals, dried fruit and nuts without adding sugar. Though less tasteful than cornflakes, muesli is the least processed breakfast cereal with higher nutrition value and fibre content. It tastes sweet, and is usually served with crispy nuts and dried fruit.
Read Nutrition Labels before Purchase
Avoid High-Sugar Products
Just as you cannot judge a book by its cover, some breakfast cereal products might not be necessarily good for you despite all the “Good for Heart Health” or “High Fibre Content” on their packages. To make a smart food choice, you need to read and understand the nutrition labels as well.
According to the HKSAR Centre for Food Safety, “low sugar” is defined as containing not more than 5 g of sugar per 100 g of food. Any food that contains more than 15 g of sugar per 100 g are considered “high sugar” and thus not recommended for consumption.
A breakfast cereal product with lower than 15 g of sugar per 100 g of solid food is actually not common in the market, let alone a low-sugar type. For example, a certain brand of cornflakes contains as much as 30 g of sugar per 100 g of solid food. In a fruit granola from a major Japanese snack manufacturer, the sugar content can reach 63.2 g per 100 g of solid food.
Most breakfast cereal products are of high sugar content. Long-term consumption may lead to weight gain and excessive blood sugar level in patients with diabetes, which in turn increases the risk of renal diseases, heart conditions and eyesight impairment.
Beware of Glycemic Index
The glycemic index (GI) is a value used to measure how much specific foods increase blood sugar levels. With low GI foods, its slow conversion into glucose results in less increase in blood glucose level after meals, making them suitable for controlling blood glucose and reducing the risk of diabetic complications in diabetic patients. They can also make patients feel full and delay hunger pangs. Cornflakes and coco pops are examples of high GI foods.
Most of the breakfast cereal products are highly processed and has minimal nutrition: they have been soaked in sugar and added artificial colouring and preservatives during the manufacturing process. A bowl of highly processed cereals is of no general benefit to health, as it were.
Choose High-Fibre, Low-Sugar and Non-Processed Breakfast cereal Products
Smart eating means consuming a wide variety of foods for full nutrition. Despite being high in sugar, most breakfast cereal products are still recommended for their high-fibre contents. According to the recommendations of the HKSAR Centre for Food Safety, the daily fibre requirement for adults should be not less than 25 g, which is unlikely to be met by consumption of a single food such as lettuce/ Chinese lettuce (less than 1 g of fibre per 100 g) or Chinese kale (about 2.3 g of fibre per 100 g, or 13.2 g per 600 g). By comparison, breakfast cereals are one of the good sources of dietary fibre, e.g. oatmeal contains less sugar (less than 2 g of sugar per 100 g) and more fibre (as high as 10 g of fibre per 100 g).
Breakfast cereals may “look” healthy for its high fibre content, but they also contain much sugar. For people who are on diet for weight loss, the rule of thumb is to read nutrition labels carefully and choose the high-fibre, low-sugar and non-processed type only. Oatmeal is a good choice for its low sugar content, especially the “whole rolled oats” type, and muesli has a low-to-middle GI index, which varies with ingredients. The wheat biscuits from the UK and Australia (not digestive biscuits) are also a good option, as they are low in sugar (less than 5 g of sugar per 100 g) and contain high fibre (up to 10 g of fibre per 100 g).