Stabilising your blood sugar is the secret to staying healthy, energised and slim, the latest research shows. This is news that hits fit women, too. If you work out, you need to know how to managethe highs and lows. Here’s why.

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Stabilising your blood sugar is the secret to staying healthy, energised and slim, the latest research shows. This is news that hits fit women, too. If you work out, you need to know how to managethe highs and lows. Here’s why.
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Of all the health-related things you worry about, blood sugar probably isn’t one of them. But groundbreaking studies are providing evidence that there is reason to worry. “Blood sugar is a primary determinant of your health,” says Dr James O’Keefe, a professor of medicine at the University of Missouri–Kansas City in the US. It affects the strength of your immune system, the quality of your sleep, and even the rate at which your body ages. But what’s most surprising is that fit women are especially vulnerable to its dips. 

Let’s back up: What is blood sugar exactly? Also known as glucose, it’s your body’s fuel, providing the main source of energy for your muscles, metabolism and brain. After you eat, glucose enters the bloodstream quickly, causing a bump in your blood sugar level. Your pancreas then revs its production of insulin, a hormone that helps cells absorb glucose and use it to function. 

When you consume meals consisting of healthy whole foods such as produce and lean meat, the rise in your blood sugar and insulin levels is small, steady and long-lasting, which is the effect you want. 

But certain types of foods – especially highly processed ones like white bread, pasta and cookies – can cause a huge spike. In addition, scientists have discovered that certain habitual factors, including when you eat your meals and how much you exercise, can also make your blood sugar level skyrocket. 

When that happens, “it’s like flooding an engine,” Dr O’Keefe explains. “The amount of glucose in your system exceeds your body’s capability to deal with it.” His research has found that an elevated blood sugar level triggers a surge in free radicals – dangerous compounds that can cause inflammation throughout the body, damage the lining of blood vessels, and cause blood clots. 

Even more, a steep rise in blood sugar prompts your pancreas to release large amounts of insulin. This sends your blood sugar and energy levels crashing, and makes your body store fat, says Dr Louis Aronne, a professor of metabolic research, director of the Comprehensive Weight Control Center at Weill Cornell Medicine in the US, and author of The Change Your Biology Diet: The Proven Program for Lifelong Weight Loss. 

Ironically, the more you use your muscles, the more sensitive they are to insulin, says Loretta DiPietro, chairwoman of the Department of Exercise and Nutrition Sciences at George Washington University in the US. That means women who work out may actually experience greater blood sugar lows more frequently than women who don’t. 

Your body on a sugar rush

Blood sugar’s effects are so wide-ranging that scientists are only beginning to fully understand their scope. One recent study from the Netherlands’ Leiden University Medical Center found that people with healthy blood sugar levels looked younger than others. According to the study authors, regularly being exposed to high blood sugar may speed up the ageing process. 

“Glucose causes collagen molecules to start cross-linking, making skin stiffer and more leathery,” explains Courtney Peterson, an assistant professor at Louisiana State University’s Pennington Biomedical Research Center in the US. If glucose levels remain elevated, the excess sugar can trigger the production of harmful compounds that have been shown to damage cells throughout the body, Courtney adds. 

Blood sugar also affects brainpower. In a study in the journal Neurology, people with healthy levels performed better in a word- recall exercise than those with higher levels. They even had more grey matter in areas of the brain associated with memory. 

“There’s evidence that blood sugar spikes lead to blood sugar lows that limit the amount of glucose your brain receives, resulting in symptoms like brain fog and fatigue,” says James Gangwisch, an assistant professor at the US-based Columbia University’s College of Physicians and Surgeons Department of Psychiatry. In response, your body may produce higher levels of stress hormones like cortisol and adrenaline, which make it harder for you to sleep at night. This creates a vicious circle:  The lack of zzz’s boosts blood sugar, increases your appetite and prompts your body to produce more cortisol or adrenaline. Over time, these influences can cause damaging inflammation, weaken your immune system, and encourage weight gain. 

How fit you are is also partly determined by blood sugar. Keeping your level stable gives you the energy you need to put in a solid sweat session. “Even mildly low blood sugar can cause some fatigue, which is detrimental to exercise,” says Barry Braun, executive director of the Human Performance Clinical Research Lab at Colorado State University in the US. 

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Doing a balancing act 

The good news is, it doesn’t take a lot of work to stabilise your blood sugar and improve your well-being. The 11 study-backed strategies that follow are easy to do but make a huge impact, giving you more energy and better health. 

Sprinkle cinnamon on your breakfast 

People who added about a teaspoon of cinnamon to hot cereal had significantly lower, healthier blood sugar for two hours after eating than those who didn’t eat the spice. There’s evidence that cinnamon prompts cells to absorb more glucose from blood and use it for energy. Stir one to two teaspoons a day into your smoothie, protein shake or oatmeal, and a half teaspoon  into yogurt or coffee. 

Drink at least four quarter cups of water a day 

Research shows that dehydration can raise blood sugar by increasing vasopressin, a hormone that boosts glucose levels. Just a little over one litre of water a day is all it takes to keep your levels steady. 

Don’t snack before a workout 

When you exercise, your muscles take glucose out of your bloodstream for fuel. When you’ve used up available blood sugar, your body burns belly fat for fuel. But if you eat too much before your sweat session, your body never needs to burn that fat. 

Go ahead and skip a snack as long as you’ve eaten within the four hours before your workout, Dr O’Keefe says. You’ll reap better results: Your blood sugar level will be low when you start to sweat, and your body will use fat for fuel instead of glucose. 

“Most people have enough energy stored as fat to fuel a 30- to 50-minute workout without any trouble,” Dr O’Keefe says. But if it’s been more than four hours since your last meal and you plan to exercise for more than 50 minutes, he recommends having a 200-calorie bite a half hour to an hour beforehand. Try a pear or a banana with some nuts for slow-burning energy. 

Combine cardio and strength 

Instead of sticking to weights one day and to cardio the next, do a half hour of each at every gym session. Aerobic exercise boosts your cells’ energy-burning ability and torches fat, while resistance training builds glucose-utilising muscle. Engaging in weight training for 30 minutes on most days reduces your risk of developing diabetes by 34 per cent over 18 years. Combining it with aerobics lowers the odds by almost 60 per cent, according to research in the Archives of Internal Medicine. 

Get moving after lunch 

If you eat and then sit for hours – which basically describes anyone with a desk job – the sugar from your meal builds up, Barry says. “But if you do something active, your cells will use that glucose for fuel, so your blood sugar level stays steadier,” he explains. 

Wait 30 minutes after finishing your last bite to give the food enough time to break down into sugar, then take a walk or do some lunges and squats, Loretta suggests. Her research shows that spending 15 minutes on activities like these can reduce post-meal blood sugar spikes and keep levels lower for 24 hours. 

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Feed your gut bugs 

“Some of the good microbes that live in your gut may help stabilise blood sugar,” Courtney says. To keep your intestinal flora healthy – especially when you’re taking antibiotics, which can wipe out gut bugs – Dr O’Keefe recommends eating fermented foods like Greek yogurt, kimchi, sauerkraut and dill pickles daily. 

Skip artificial sweeteners

Just like the real thing, artificial sweeteners cause the blood sugar to rise. In an Israeli study, participants’ levels soared after just one week of eating foods containing them. The study authors believe that they affect gut bacteria in a way that makes the body more intolerant to glucose, which boosts blood sugar. 

Follow the 50-36-14 plan

Blood sugar control is markedly worse at 7pm than at 7am, according to a recent study from Pennington Biomedical Research Center in the US. “Different parts of our physiology peak at different times,” explains Courtney, one of the study’s authors. “The pancreas produces insulin faster first thing in the morning to help lower blood sugar, and it slows down as early as 3pm. That’s a problem, because most people eat 40 per cent of their daily calories at night, when their bodies can’t keep their blood sugar as stable.”  

To prevent this effect, eat a big breakfast that’s about 50 per cent of your daily calories, a lunch that’s about 36 per cent of your calories, and a small dinner that’s just 14 per cent of your calories. In an Israeli study, women who did this saw reductions in their levels of glucose, insulin, and appetite- triggering hormones. They also lost weight. Courtney suggests eating dinner at least three hours before bedtime to give yourself plenty of time to digest your food. 

Have a cocktail with dinner

Sipping a drink with an evening meal reduces blood sugar spikes by up to 37 percent, research in the American Journal of Clinical Nutrition found. “Like exercise, a modest amount of alcohol improves the body’s ability to utilise glucose,” Dr O’Keefe says. But the benefit disappears with a second drink. 

Save bread for last 

Your blood sugar will be more stable if you eat vegetables and protein-rich foods first and carbohydrates last, a new study reports. “The difference is tremendous,” says Dr Aronne, the lead researcher. “Vegetables and protein slow the release of carbohydrates from the stomach, which keeps glucose from spiking. They may also trigger the release of a blood sugar–controlling hormone in the gut.” 

Dip that bread in olive oil and vinegar 

Adding one or two tablespoons of vinegar to a meal with white bread or rice lowers blood sugar by 25 to 35 per cent, according to research in the Journal of the American College of Cardiology. Experts believe the acidity of vinegar slows digestion, preventing glucose from surging. 

Also, the monounsaturated fats in olive oil help regulate the body’s insulin response and blood sugar control. Extra-virgin olive oil has more of the chemical components found in whole olives, which are the most beneficial.