What are the best low-glycaemic index foods?

When assessing a food’s glycaemic index, it is crucial to consider the blood glucose levels associated with optimal health. Normal blood glucose levels, defined as between 0.70 g/l and 1.10 g/l when fasting, should remain below 1.40 g/l 1½ hours after a meal. These parameters serve as benchmarks for assessing the impact of dietary choices on blood sugar regulation and highlight the importance of prioritising foods with a low glycaemic index in order to maintain blood glucose levels within the recommended limits.

A glycaemic index is considered low when it is below 50, whilst it is classified as high when it exceeds 50. This measure, developed by Dr David J Jenkins, a professor at the University of Toronto, enables us to predict the impact of a food on blood sugar levels. Foods are classified according to their glycaemic index as follows:

• Very low-glycaemic index food: between 0 and 20

• Low-index food: between 20 and 50

• Medium-glycaemic index food: between 50 and 70

• Foods with a high GI: above 70

The GI, short for Glycaemic Index, combines the term ‘index’, referring to a rate, with ‘glycaemic’, relating to blood glucose levels and therefore to sugar. Thus, the glycaemic index serves as a tool for measuring the level of sugar, or glucose, in the blood. This classification provides a solid basis for understanding how dietary choices influence blood glucose levels and, by extension, metabolic health. Certain ingredients, such as maltodextrin, generally have a high glycaemic index and can cause a rapid rise in blood sugar levels.

Why choose low-glycaemic index foods if you’re not at risk of diabetes? Firstly, because it’s better for your general health, but also to boost your energy levels and avoid those infamous post-meal slumps. We explain everything: 

To limit insulin production 

Choosing low-glycaemic index foods effectively reduces insulin production. Insulin, a key hormone in regulating blood sugar levels, is released in response to the consumption of carbohydrates. High insulin levels, resulting from eating foods with a high glycaemic index, can lead to insulin resistance, a condition associated with type 2 diabetes. By prioritising foods with a low glycaemic index, you reduce insulin release and thus help maintain optimal hormonal balance.

To reduce glucose spikes

The higher a food’s glycaemic load, the greater the subsequent glucose spike will be. This glucose spike is often responsible for the ‘energy slumps’ experienced after lunch.

By choosing foods with a low glycaemic index, you limit these glucose spikes, resulting in a more stable release of energy throughout the day. Stable blood sugar levels not only reduce post-meal tiredness, but also help improve concentration and maintain a steady energy level, whilst reducing the urge to compensate for the subsequent dip with sugar-rich snacks. Say goodbye to the vicious cycle of sugar! 

TIP

To limit spikes in blood glucose and regulate blood sugar levels, add a tablespoon of apple cider vinegar to a glass of water. Drink the glass before eating and you’ll find you no longer experience that post-meal slump! And if you don’t like the tartness of vinegar, there are versions with honey that are milder and more pleasant on the palate.  

To slow down weight gain

Frequent consumption of high-glycaemic-index foods is often linked to weight gain, due to excessive insulin secretion. This is because, whilst the body uses the insulin it produces, it cannot use it indefinitely. If there is too much insulin in our bodies, this excess will be stored and converted into fat. 

By choosing foods with a low glycaemic index, you can help prevent excessive fat accumulation. Foods with a low glycaemic index, which are often rich in fibre and nutrients, promote a feeling of fullness, thereby limiting overeating and potentially preventing unwanted weight gain. 

Remember that it is essential to follow a healthy, varied and balanced diet, combined with regular physical activity. 

It’s worth noting that 100 is equivalent to pure sugar, so foods with a high glycaemic index have almost the same effect on your health as if you were consuming glucose directly. 

Which starchy foods have a low glycaemic index? 

Bad news for all lovers of pasta and Italian cuisine: most starchy foods are classified as having a high GI. These include well-known brands of pasta, gnocchi, breakfast cereals, puff pastry and, more generally, anything containing wheat.  

Instead, opt for wheat and its derivatives, as well as wholemeal flours, which are less sugary: quinoa, bulgur, Ebly or brown rice. Low-GI starchy foods include: 

• Wheat bran and oat bran (15)

• Soya flour (25)

• Vermicelli (35)

• Buckwheat flour (40)

• Cooked sweet potatoes (46)

• Wholemeal spaghetti (48)

• Pasta cooked al dente (49)

• Egg pasta (cooking time 4–5 mins) (49)

TIP

Instead of having cereal and sweetened yoghurt for breakfast, opt for plain soya yoghurt with oat bran and agave syrup to sweeten it. You’ll feel fuller straight away and won’t get peckish before lunch! 

Which vegetables have a low GI? 

All vegetables naturally have a low glycaemic index, and sometimes even a very low one. However, once cooked, their glycaemic index rises, changing from low to high. You should therefore eat your vegetables raw wherever possible to benefit from all their fibre and antioxidant properties. Low-GI vegetables include:

• Swiss chard (1)

• Broccoli (1)

• Asparagus (15)

• Mushrooms (15)

• Green beans (15)

• Leeks (15)

• Peppers (15)

• Rocket (15)

• Raw tomatoes (15)

• Aubergines (20)

• Homemade ratatouille (20)

So don’t hold back on green vegetables and fresh vegetables, which you can use to make lovely seasonal salads. Don’t miss out on cooked vegetables either; they’re also excellent for your health, although they have a slightly higher GI. 

Which fruits have a low GI? 

Fruits generally have a fairly high glycaemic index because they contain both glucose and fructose, the sugars found in fruit. However, some fruits are lower in sugar than others; for example, red berries have a low GI. Here are the ones to prioritise: 

• Avocado (10)

• Blackcurrants (15)

• Lemon (25)

• Grapefruit (25)

• Blackberries (25)

• Blueberry (25)

• Raspberry (25)

• Fresh apple (35)

• Pear (38)

• Strawberry (40)

As with vegetables, it is best to eat whole fruit rather than processed fruit to benefit from its fibre content.

Which meats and fish are lowest in carbohydrates?

When it comes to meat and fish, there’s no need to deprive yourself. Meat is rich in iron, whilst fish is rich in omega-3 and selenium. However, to ensure they aren’t too fatty or too sweet, avoid very rich sauces. Low-GI meats and fish include: 

• Beef

• Chicken

• Pork

• Lamb 

• Eggs

• Salmon

• Tuna

• Sardines

• Prawns

For vegans and vegetarians, pulses are an excellent alternative, being both high in fibre and low or very low on the glycaemic index. The key is to vary your food sources, so do treat yourself and try new things. 

Which alcoholic drinks and other beverages are lowest in sugar?

Fizzy drinks and some mixed fruit juices are known for their high sugar and calorie content. If you’re looking for refreshing drinks without sending your blood sugar levels skyrocketing, we recommend opting for tea, coffee or fruit juices instead. Low-GI drinks include: 

• tomato juice (38)

• carrot juice (43)

• Prune juice (43)

• apple juice (44)

As for alcohol, some drinks contain no sugar at all, but should still be consumed in moderation: 

• Vodka (0)

• Gin (0)

• Whisky (0)

• Cognac (0)

• Rum (0)

Although they have a low GI, they are nevertheless much higher in calories than most other alcoholic drinks, with an average of 100 calories per 45ml. 

Which bread should you choose if you’re on a low-GI diet? 

Contrary to popular belief, bread isn’t always packed with sugar or bad for your health. To reap all its benefits, it’s important to know how to choose it wisely: 

• Oat bran bread

• Wholemeal bread

• Sourdough rye bread

• Wholemeal bread

For a white baguette high in sugar and gluten, expect a glycaemic index of around 62 per 60g of bread. When paired with chocolate spread, the total rises to 72 – a very high index! 

Which snacks have the lowest glycaemic index? 

Say goodbye to cakes, muffins, cereal bars and other processed, sugar-packed snacks: instead, opt for nuts, which are good for both your brain and your stomach. 

• Almonds 

• Cashew nuts

• Pistachios

• Walnuts 

• Macadamia nuts

A handful of almonds makes the perfect snack if you’re feeling peckish between lunch and dinner. You can sprinkle them over your soya yoghurt or add a few walnut halves to your salads to add a bit of texture and colour. 

Which cheeses have a low glycaemic index? 

If you’re a cheese lover, here’s some good news: cheese isn’t particularly high in carbohydrates, and hard cheeses top the list! But be careful – just because they have a fairly low glycaemic index doesn’t mean they’re low in calories or fat; quite the opposite, in fact. It’s therefore best to limit yourself to a portion of 30g per person per day. Among those with a low GI are:

• Parmesan 

• Comté

• Brie

• Camembert 

• Goat’s cheese 

The low glycaemic index of cheeses is due to the maturing process. The longer the cheeses are matured, the less lactose they contain; and as it is the lactose that is rich in carbohydrates, the glycaemic index of these cheeses decreases. 

Laura is a health, beauty and lifestyle writer. Passionate about travel and gastronomy, she shares all her nutritional tips on how to combine pleasure with wellbeing. Through her articles, she is committed to providing you with meaningful information and practical advice to nourish your body and mind.