The level of increase in glucose in your blood after you eat and drink is an important indicator of metabolic health. It is normal for your blood glucose to rise after you eat and then fall again as your body takes in the sugar from your blood to use for energy or to store. However, blood glucose levels that are continually too high are not good for us.
Studies show if we want to manage and maintain a healthy weight, we should be concentrating on flattening our post-meal glucose curves and not counting calories. By flattening your blood glucose curves, you can consume more calories and lose more fat compared to people who eat fewer calories but do not concentrate on flattening their glucose curves. Avoid having blood sugar spikes and your blood glucose curves will flatten1.
When we flatten our blood glucose curves, we activate a cascade of benefits including less cravings, reduced hunger and our time spent in fat burning mode is improved2.
The hormones insulin and glucagon act as a partnership and are responsible for keeping the blood glucose in a healthy range. When blood glucose increases, insulin activates the cells to take up sugar and blood glucose is lowered. When blood glucose drops too low; glucagon stimulates the release of glucose stored in the liver into the blood. Together they ensure cells always have enough energy to function.
Glucose is essential for our bodies as an energy source, and we have systems to process and store glucose for future use. The liver and muscles are the primary stores (glucose stored as glycogen), and we can store around 15g of glycogen per kg body weight (about 1kg for a 70kg individual), and this is facilitated by insulin. The problem comes when we eat too much or eat high GI foods as the insulin also pushes glucose into adipose tissue (insulin doesn’t preferentially store energy anywhere, but 75% of the glucose-transporters are in muscles, 25% in fat and if we are eating the right amount, the energy stored in adipose tissue gets burnt). Sugary foods also contain fructose, which is processed by the liver, and when there are excess calories will be converted and stored as fats rather than being converted to glucose (which is what happens if you aren’t overeating sugar/fructose).
When blood glucose is continuously high our insulin levels are chronically elevated and losing weight becomes much harder. When we decrease our blood glucose level, our insulin levels drop too, and insulin reduction is essential and always precedes weight loss3. If we don’t keep our insulin in check, we move into fat storage mode instead of fat burning mode.
Learning how to balance your blood sugar and stabilize post-meal blood glucose spikes can be easy and sustainable with the right support in place. Using the following tools will support a healthy blood sugar and insulin response.
Eat your food in the right order:
Calories from the various food groups, carbohydrates (starch and sugar), protein, and healthy fats each have a remarkably different effect on our blood sugar. To best stabilize your post-meal blood sugar spikes, we need to eat the various food groups in a certain order. According to researchers the best way to lower glucose spikes is to eat your vegetables first then your protein and fats and finally carbohydrates last4.
Carbs and sugar are quickly broken down into glucose and absorbed into the blood stream causing a rapid spike in blood glucose. If carbs and sugars are consumed on their own the sugar spike will be even higher. Fat and protein take longer to digest than carbs and delay gastric emptying, slowing down the rate at which carbs will exit the stomach. Fiber from vegetables does not get broken down into sugars and passes straight to the gut. Fiber also slows digestion and reduces the availability of enzymes that break down the carbs into glucose; if the carbohydrate can’t be broken down into glucose it can’t be absorbed from your gut into your blood as the molecules are too large to get into the body. As fiber is not digested it moves through the intestines as a viscous mesh, trapping other nutrients (e.g., fats) as well as triggering the release of hormones that make you feel fuller for longer. It also becomes food for the microbiome that converts it into short-chain fatty acids that can also help curb our appetite and lower our blood glucose.
Flatten your Curves with a Low Glycemic Index (GI) Breakfast
The Glycemic Index (GI) is a ranking from 1-100 and relates to how quickly foods make your blood glucose levels rise after consuming them. Low GI foods are more slowly digested and cause a gradual increase in blood sugar. In contrast high GI foods are quickly digested and cause a rapid increase in blood sugar.
A protein-rich breakfast enables you to start the day in ‘low GI’ mode also known as fat burning mode. This gives you sustained energy and you will feel less hungry between meals. Restricting carbohydrates at breakfast is a simple strategy to reduce rapid and large increases in blood sugar levels.
If you start your day with a low GI breakfast, not only will your blood sugar response to your breakfast be healthier but you also set up your body to better cope with the next meal. So even if you have a high GI lunch, your blood sugar response will be milder if you started your day in ‘low GI’ mode. This response is known as ‘the second meal effect’, a phenomenon where the GI of one meal can influence the glycemic response to a subsequent meal. The second meal effect not only benefits a lower postprandial (=post-meal) glucose response but also extends to weight management,5,6.
Dress Your Carbs
You can reduce how much and how quickly you absorb glucose from sugars and carbs by combining them with fiber, protein, and fats.
Eating carbs naked, on their own away from other food groups, spikes our blood glucose and although we initially feel full, we quickly become hungry again as our blood sugar rises and falls. Over time, a high intake of sugar can damage hunger and fullness cues and heighten cravings.
Fiber, healthy fats, and protein help to shorten the glucose spikes in response to carbs and sugars. Protein, healthy fats, and non-starchy vegetables keep us fuller for longer because they take longer to digest, and they have a minimal impact on blood sugar7.
To dress your carbs, simply add a green starter or vegetables before every meal, and combine a snack with cheese or yoghurt, or eat a snack with a handful of nuts and seeds.
Eat your sweet treats after your main meal
After eating something sweet we feel an initial energy boost as the feel-good hormone dopamine in the brain is released. Sweet food contains sucrose which is made up of fructose and glucose molecules. Sweet foods cause both a spike in glucose and a spike in fructose. However, glucose can be stored in the liver and muscles as glycogen, but fructose can only be stored as fat.
Eating something sweet at the end of a meal will minimize the resulting glucose spike compared to eating something sweet as a snack away from meals and on an empty stomach. This is because carbs raise our blood sugar but if we consume them after our veggies, fat, and protein they have a smaller effect on our blood glucose.
The period after eating is called the postprandial state and our metabolism is at its busiest during this time metabolizing nutrients and supplying our tissues with essential metabolic fuels. When we are not in the postprandial phase our insulin levels drop helping us to burn rather than store fat.
Snacking trains your metabolism to want more snacks. The more times you eat in a day the more times you will spend in fat storing mode instead of fat burning. If you want a snack, it is better to have a savoury one to avoid an unhealthy blood sugar spike. Recent studies show we can increase our metabolic flexibility and lose weight by eating larger meals less often rather than snacking every few hours8.
Exercise after you eat
You can flatten the glucose curve of a meal by taking a walk after eating. If we remain sedentary after food our glucose will cause a spike. If we exercise the glucose in our blood is taken up by the muscles and the glucose spike is reduced. We have up to 70 minutes after eating to gain the benefits from exercise and lessen our glucose curve. Movement flattens our glucose spike without increasing our insulin levels because if our muscles are busy contracting, they don’t need insulin to take up glucose. Just a ten-minute walk is enough to gain the benefit.
Exercising before a meal also has benefits for reducing our spikes but exercise after a meal flattens the glucose curve more. Exercise after a meal can reduce cravings, ease mood swings and ward off afternoon tiredness9.
A steady blood sugar means your cells don’t get overloaded with insulin, which gives your body time to burn fat for energy in between meals and overtime results in weight loss.
Making simple changes to the way you eat helps your body to work more efficiently and you can lose weight without giving up the foods you love.
If you are trying to steady your blood sugar, improve your health, and lose weight, try these tools to flatten your glucose curve:
- Have a small salad or plate of veggies and some healthy fats before each meal
- Eat a savory breakfast rather than a sweet breakfast
- Have your dessert or sweet treat after a meal and never on an empty stomach
- Choose whole fruit over juice so you get the benefit of the fiber
- During a meal, eat the veggies first, then the proteins and the sugars and carbs last
- Never eat sugar or carbs on an empty stomach
- Never eat naked carbs, instead always eat with them with healthy fats and protein
- After each meal, go for a 10-minute walk. Any 10-minute exercise followed in 70 minutes after eating will have a positive impact
This Blog is inspired by the international bestseller Glucose Revolution by Jessie Inchauspé.
References:
- Laura R Saslow et al., Twelve-month outcomes of a randomized trial of a moderate-carbohydrate versus very low-carbohydrate diet in overweight adults with type 2 diabetes mellitus or prediabetes. Nutrition & Diabetes 7, no.12. 2017. https://www.nature.com/articles/s41387-017-0006-9
- Jessie Inchauspé, Glucose Revolution: The life-changing power of balancing your blood sugar. London: Short Books, Octopus Publishing Group Ltd, 2022
- N M Wedick et al., Insulin resistance precedes weight loss in adults without diabetes: the Rancho Bernardo Study. American Journal of Epidemiology, 15 June 2001, 1199
- Domenico Tricò et al., “Manipulating the sequence of food ingestion improves glycemic control in type 2 diabetic patients under free-living conditions,” Nutrition & diabetes 6, no. 8 (2016): e226-e226, https://www.nature.com/articles/nutd201633/.
- Courtney R Chang et al., Restricting carbohydrates at breakfast is sufficient to reduce 24-hour exposure to postprandial hyperglycemia and improve glycemic variability. American Journal Clinical Nutrition. 2019 May 1;109(5):1302-1309. https://doi.org/10.1093/ajcn/nqy261
- Paula Chandler-Laney et al., “Return of hunger following a relatively high carbohydrate breakfast is associated with earlier recorded glucose peak and nadir,” Appetite 80 (2014): 236-241, https://www.sciencedirect.com/science/article/abs/pii/S0195666314002049.
- The effects of functional fiber on postprandial glycemia, energy intake, satiety, palatability and gastrointestinal wellbeing: a randomized crossover trial,” Nutrition journal 13, no. 1 (2014): 1-9, https://nutritionj.biomedcentral.com/articles/10.1186/1475-2891-13-76.
- Hana Kahleova et al., “Eating two larger meals a day (breakfast and lunch) is more effective than six smaller meals in a reduced-energy regimen for patients with type 2 diabetes: a randomized crossover study,” Diabetologia 57, no. 8 (2014): 1552-1560, https://link.springer.com/article/10.1007/s00125-014-3253-5.
- Andrew N Reynolds et al., “Advice to walk after meals is more effective for lowering postprandial glycaemia in type 2 diabetes mellitus than advice that does not specify timing: a randomized crossover study,” Diabetologia 59, no. 12 (2016): 2572-2578, https://link.springer.com/article/10.1007/s00125-016-4085-2.