Guest Post Sally Marchini, Dietitian
In my post benefits of including low-glycemic index carbs in your diet I mentioned aiming to include at least 1-2 serves in every meal to help to stabilise your blood sugar levels and energy levels and to keep you satisfied for longer as well as those many other benefits we covered.
So the great thing about making the change to low-GI is that it’s not a diet but more a way of eating. It’s not restrictive, but if you can learn to recognise when foods are likely to have a lower glycemic index, then you’ll be able to make better choices. It doesn’t cut out any major food groups so we’re still following the Australian Dietary Guidelines.
The Glycemic Index Foundation advises us “Only about half the carbohydrate needs to be exchanged from high to low GI to derive health benefits” so it’s not about avoiding the higher ones altogether, just ensuring at least that moderate balance erring to the low side.
In today’s blog I’ll run through those five major food groups and help you to choose carb sources with a lower GI.
1) Vegetables and legumes/beans – when choosing starchy vegetables aim for sweet potato or corn in preference to white potato (unless it’s the Carisma potato that has been bred to have a lower GI) and aim to include the legumes and beans as often as you can (perhaps I’ll do a separate blog on them down the track – another of my favourite topics!).
2) Fruit – fruits such as apples, pears, citrus and stone fruits tend to be lower, and under-ripe bananas are too.
3) Grain (cereal) foods – this is the biggie! The more whole grains in any of these products, the slower they’ll digest.
- If you can aim for foods with less processing such as traditional oats rather than quick cook oats or processed cereals.
- Choosing staples such as wheat-based pasta, barley, quinoa over rice and potatoes
- If you do choose rice, get Basmati or Doongara and watch that it’s not overcooked
- In breads, the grainier you can get, the lower they’ll be. Traditional sourdough is also low, and if you’re a white bread addict try Tip Top’s ‘The One’ or the pink WonderWhite high-fibre bread. It’s important to remember that it’s not just the fibre that lowers the GI, but the type of fibre, hence wholemeal being high-GI.
4) Protein foods – remembering that only carbs can have a GI rating, again we focus on trying to include legumes and beans each day as they will lower the overall GI of the meal you’re eating.
5) Dairy and alternatives – other than cheese (virtually no carbohydrate) all dairy foods have a low-GI and are nutritious foods to include for many good reasons. It’s important to get your 2.5-4 serves every day. All the soy milks also have a low-GI.
You can also ‘manipulate’ the GI of your meal by several methods:
1) You can lower the overall GI of the meal by including a mixture of low and high GI sources, for example if you wanted a white potato, you could add some low-fat yogurt with chives and seasoning to it, or by finishing the meal with a dairy based dessert such as low-fat yogurt or ice-cream.
2) If you add a tablespoon of vinegar or lemon juice to your meal, you can lower your post-prandial (after meal) blood glucose readings by as much as 30%. That’s easy to achieve by enjoying a salad with dressing made from vinegar or lemon juice, by adding a tablespoon of vinegar to your mashed potato (quite tasty), or even adding the lemon juice to the water you’re drinking with the meal.
3) Adding quality proteins and good fats to your meals will also slow the digestion of the carbohydrate part of the meal. Using a handful of nuts in your meal can help you achieve this too, like added to stir-fries or salads. (Remember though that proteins and fats will add kilojoules/calories to whatever you’re eating so may affect your weight.)
4) Adding soluble fibre and resistant starch sources will again slow the digestion of your carbs. There are lots of foods that are higher in soluble fibre, and many of them are low-GI carbs themselves for that reason. Some that might not feature as carbs that you add include asparagus, brussels sprouts, broccoli, frozen peas, turnip, carrots and onion.
This resource on Carbohydrates and the Glycaemic Index by the Baker IDI Heart and Diabetes Institute also has some good ideas. Page 2 provides a similar guide to what we’ve provided here, and Page 3 offers some meal ideas to help you add the low-GI carbs into your day.
And the Glycemic Index Foundation has a fabulous Frequently Asked Questions page that I encourage you to read through.
Next time we’ll talk about the glycemic load as that can help to bring this topic all together.
Until then I challenge you to think about whether you can lower the GI of your food choices 🙂
Sally is owner of her private practice (Marchini Nutrition), and has had type 1 diabetes for close to 40 years and coeliac disease for many years too.