Guest Post Sally Marchini, Dietitian
By popular demand I think that this topic deserves a blog to help explain some of the ‘stuff we hear’ around carbohydrates and type 2 diabetes.
I’d also encourage people with type 1 diabetes to read this, because some of the points made are also relevant for us!
Up front I will remind readers that everyone has individual requirements and should see an Accredited Practising Dietitian for a personalised consultation. This is a ‘general guide’ only.
Firstly, we need to understand what ‘low’ means in such a context. In my experience as an Accredited Practising Dietitian, people tend to associate ‘low’ with ‘virtually no’ carbohydrate. We’ll also look at some of the evidence that shows that ‘low’ carb diets can help with glucose control in type 2s, and why when drugs (other than metformin or SGLT2-inhibitors) are introduced it’s important to ensure more (quality) carb intakes as advised by your health professionals. And lastly (but certainly not leastly) we’ll review how, based on the Australian Dietary Guidelines, it’s possible to have a nutritionally balanced diet while watching your carb intake.
What does ‘low’ carbohydrate mean?
If you ask some people what they think ‘low carb’ means, you may hear that it’s about cutting carbohydrates out as much as possible. Straight up as a dietitian my alarm bells ring as carbs feature in all five of the food groups that we need for nutrients to ensure our wellbeing: vegetables (starchy vegetables like potato, sweet potato and corn), fruit, dairy, protein (when the likes of legumes are included, and especially in vegetarian diets) and of course, the important grain/cereal foods.
The American Diabetes Association defines a low-carb diet as 130g of carb per day. Does that surprise you?? The ‘trick’ with low carb diets is therefore to know how to choose your carbs wisely so that you’re still meeting your nutrient requirements, and also to know what to replace that carb energy with (remembering that carbs, proteins and fats make up our daily energy intake) so you don’t get too hungry and be encouraged to ‘cheat’.
Remembering that there’s 15g of carbohydrate in an ‘exchange’ or ‘serve’ that gives us close to 9 carb serves across the day.
If you’re on medication that helps your body to produce more insulin, or you’re providing insulin yourself on a fixed dose then this idea is dangerous to your health so please speak to your health professionals before making any changes to your diet.
Some benefits of lower carbohydrate diets
Of course we know that all carbohydrates break down to glucose which is the fuel needed by our bodies, but in modern diets often too much (and poor quality) of this ‘fuel’ is provided which can cause stress to our organs and worsen our diabetes control. So understanding the benefits of a lower carbohydrate diet can help us to stick with it for longer and balance the rest of our diets more easily.
Some of those benefits may include:
- Lower incidence of high blood glucose levels (hyperglycemia)
- Lower amounts of medications need to control hyperglycemia
- 130g/day is a sustainable amount, meaning it’s easier to stick to in the longer term
- Putting your pancreas under less stress to produce insulin, thereby helping it to keep working for longer
- By ensuring your 130g/day is nutritious and low-GI carb you may also improve your blood fat levels (cholesterol/triglycerides) which will lower your risk of cardiovascular disease
- It doesn’t necessarily lead to weight loss – that depends on your total energy intake.
How do you manage it best?
Again I will mention how important having a personalised consultation with your Accredited Practising Dietitian is because everyone is different in many ways. Here I will make suggestions that I hope will help to get your head around combining the idea of low carb into your daily routine while still meeting the nutritional requirements as outlined in the Australian Dietary Guidelines foundation diet (see page 2).
In a nutshell, it’s about only choosing your carb sources from the 5 food groups and balancing that out with quality proteins and healthy fats. I encourage you to re-read the previous blogs I’ve written on those topics as highlighted.
Remembering that 130g/day equates to close to 9 carb exchanges/serves, your day might start to look a bit like this:
Breakfast: ¼ cup of raw rolled oats (1 serve carb) served with 125ml light milk (half a serve), a small banana (85g – 1 carb serve) and a tablespoon of LSA mix (for extra fibre/protein) = 2.5 serves total
Morning Tea: A 100g tub of low-fat yogurt = 1 serve total
Lunch: A sandwich made on wholegrain bread (the grainier the better – 2 serves) made with a protein serve and as much non-starchy veg as you can handle, either on the sandwich or as a side, using half an avocado as the spread (for your good fats), and a piece of fruit such as an apple or pear (both good low-GI fruits – 1 serve) = 3 serves total
Afternoon Tea: A 30g handful of mixed unsalted nuts = not worth counting carb-wise
Dinner: Remembering the balanced plate being one quarter carb, one quarter protein and half non-starchy vegetables, this works with so many meals. Aim for your carb serve to = 2 serves total
Supper: You’ve still got half a carb serve up your sleeve. I would encourage something like half a slice of grainy toast with peanut butter on it to give you the energy to get you through the night, but half a serve of low-fat dairy would also work well, or even a couple of squares of dark chocolate if you fancied it = 0.5 serves total
In this example you can see that we’ve incorporated 9 carb serves/exchanges and yet have included quality carbs at every meal.
Some final tips
- Remember to include protein and some non-starchy veg with every meal.
- Rice and pasta can be problematic a serve size is so small. Something I recommend that works for many people is to include the carb serves in the form of legumes (lentils, chickpeas, kidney beans, etc) in the pasta sauce and use low-carb alternatives such as those made from konjac root, or make pasta/rice out of vegetables such as grated zucchini or carrot or cauliflower. I sometimes serve my pasta sauces on mashed cannellini beans and frozen spinach (warmed of course!) and find it’s very satisfying.
- Don’t forget to exercise! If the point of minimising your carbs is to control your BGLs, then even as little as ten minutes exercise after meals can make a fantastic difference to your readings. Do some self-experimenting about how much your BGLs drop after say 10, 20 or 30 minutes walking after meals, and then if you want to include more quality carbohydrates in some meals, you’ll know how to manage better.
I hope this has proved useful for you, and that you have a better understanding of how a low-carb (130g/day) might help with your diabetes control. Of course please ask any questions below and I’ll be happy to address them for you.
Sally is owner of her own private practice (Marchini Nutrition), and has had type 1 diabetes for close to 40 years and coeliac disease for many years too.
Edited by Helen Wilde, Moderator, Diabetes Can’t Stop me on 4/04/17