Eat your vegetables! says the archetypal mom. Addendum: Eat your vegetables first! Gregory Rec/Staff Photographer
Scientists have found that it’s not just the type of foods you eat that can influence your health and metabolism, but the order in which you eat them.
A growing number of studies have found that eating fiber-rich vegetables, protein or fat at the start of a meal, and eating refined carbohydrates like rice, bread or pasta last, can improve blood sugar levels and stimulate higher levels of hormones that promote fullness and satiety. Some preliminary studies suggest it may even help with weight loss.
This strategy, known as food order or meal sequencing, runs counter to the way people often eat. It suggests that it’s better to reach for the basket of bread or chips at the end of a meal rather than eating these high-carb, low-fiber foods at the beginning.
The recent studies on food sequencing have been small but rigorous. They have found that starting meals with protein, fat or fiber-rich vegetables instead of high-glycemic carbs that spike blood sugar levels tends to slow down the digestive process. It reduces the speed at which food leaves your stomach and enters your small intestine, a process known as gastric emptying, which makes you feel fuller longer.
“We’re not asking people to fast, skip meals or avoid specific kinds of foods,” said Domenico Tricò, assistant professor at the University of Pisa in Italy, who studies nutrition and diabetes. “We’re just saying please eat low glycemic foods at the beginning of the meal and then eat the rest at the end.”
The studies add to a growing shift in how nutrition researchers think about food and its impact on our health. They are finding that there are many factors beyond just the nutrients and calories in food that matter, such as the extent to which foods are processed, the time of day we eat them, and precisely how we consume them.
Studies show that eating vegetables first can cause your body to secrete higher levels of GLP-1, a satiety hormone that our guts release in response to meals. (GLP-1 is the same hormone that the popular weight loss and diabetes drugs Wegovy and Ozempic are designed to mimic). This strategy can also help prevent large and sustained elevations in blood sugar levels after meals, some studies suggest.
Researchers have found that starting each meal with vegetables or protein can be particularly helpful for improving blood sugar control in people with Type 2 diabetes or prediabetes, a precursor condition that increases a person’s risk of developing the disease.
In one study in Japan, where rice is a dietary staple, researchers found that people with Type 2 diabetes who were instructed to eat vegetables before carbohydrates at every meal for a period of two years had greater improvements in their long-term blood sugar control compared to a control group.
In other studies, Daisuke Yabe, an endocrinologist, looked at what happened when healthy adults and people with Type 2 diabetes ate meals of white rice, fish and meat but in different orders on different occasions. He found that people produced higher levels of satiety hormones and had smaller spikes in their blood sugar levels. They also had a significantly slower rate of digestion when they were told to eat the fish or meat portions of their meals first and the rice portions last, compared to eating the rice first.
“It was very striking to us,” said Yabe, a professor and chairman of the department of diabetes, endocrinology and metabolism at the Gifu University Graduate School of Medicine in Japan. “You eat the same foods, but change the meal sequence, and GLP-1 secretion goes up.”
Tricò, the University of Pisa researcher, said there’s no one-size-fits-all approach to diet. But he’s demonstrated in several studies that food order has surprising effects on blood sugar and hormone levels.
He recommends the practice to his patients with diabetes, obesity and other metabolic diseases because it’s relatively simple to follow and doesn’t require radically changing the foods that you eat. “This particular strategy is typically well accepted,” he said.
Nutrition experts say you shouldn’t obsess over every meal that you eat, and eating foods that you enjoy is an important part of life. But if you routinely eat high glycemic foods (refined carbohydrates like white bread, pasta and sugary foods), there are things you can do to mitigate their effect on your metabolic health. For some people, this might include incorporating some elements of the food sequencing strategy and trying to reduce refined carbs.
Eat nuts first. Consider having a small handful of almonds, which contain fiber and healthy fats, before eating a bagel or muffin for breakfast. A study found that people who were assigned to eat about 20 grams of almonds (less than one handful) before their daily meals over 16 weeks significantly lowered their body fat, including the dangerous visceral fat that surrounds internal organs, compared to a control group. Another study found that eating an almond “appetizer” or “preload” (about half an ounce, or roughly 12 almonds) before meals improved blood sugar responses in people with prediabetes.
Start with a salad dressed with olive oil. If you’re going to eat fast carbs for lunch or dinner (such as pasta or a turkey sandwich on white bread), preload with a salad. It contains heart-healthy fats and fiber, which can slow digestion, improve blood sugar levels and promote satiety. “You might end up eating a smaller portion of pasta because you’ll be less hungry,” said Tricò said.
Eat your vegetables and protein portions first. In a small study in the journal Clinical Nutrition, researchers found that when people were fed meals of chicken, vegetables and white rice, they produced high levels of satiety hormones and had smaller and more gradual elevations in blood sugar compared to when they ate these foods mixed together or in different orders.
Limit your intake of high glycemic foods. That doesn’t mean you should never eat french fries, white bread, potato chips or mashed potatoes, said Mario Kratz, a former clinical researcher at the Fred Hutchinson Cancer Research Center in Seattle and the founder of Nourished by Science, a website that promotes evidence-based nutrition for the prevention of chronic disease. But ideally, they shouldn’t be a part of your everyday meals. “In most cases they’re not nutritionally valuable foods anyway,” he added.
Don’t eat “naked” carbs. These are simple carbs that are eaten with little or no fat, protein or fiber. Some examples would be toast with jam, a plate of crackers or tortilla chips, or a bowl of sugary breakfast cereal with nonfat milk. Because these foods are rapidly absorbed and digested, they can cause your blood sugar to spike and plummet, creating a cycle of hunger and cravings. Ideally, you should pair these foods with healthy fats, protein and fiber. You can do this, for example, by spreading peanut butter on your toast, eating your crackers with cheese and almonds, or dipping your chips in guacamole.
Christiani Jeyakumar Henry, a professor of biochemistry at the National University of Singapore, said the strategy of eating vegetables before refined carbs may be particularly useful in countries with rising diabetes rates where rice is also a staple.
“For every diabetic anywhere in the world, there are two or three undiagnosed prediabetics on their way to becoming diabetic if they don’t control their blood glucose levels,” he said.
Kratz cautioned that the “carbs last” strategy is not always practical, but most people can pair simple carbs with healthy fats, protein or fiber.
“You shouldn’t be totally obsessing, because if you do, you’ll just end up cutting out all carbs,” Kratz said. “The key is to find ways that you can modify your meals a little so they’re still culturally acceptable while also reducing the extent to which they are naked carbs. I think for most people, that’s the way to go.”
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