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Does the Order of Food You Eat Matter for Blood Glucose Control?

Key Takeaways

  • Food sequencing refers to the specific order of eating within a meal where an individual consumes high-GI foods last.

  • Food sequencing results in gentler postprandial glucose elevation in individuals with and without diabetes because of slowed gastric emptying and an increased secretion of GLP-1 hormone. 

  • However, food sequencing’s benefits on blood glucose control don’t appear to last beyond the postprandial state. 

  • In the grand scheme, a more meaningful method of blood glucose and weight management control would be adopting a well-rounded approach that includes diet, exercise, and lifestyle changes.

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Imagine two plates with the same portions of white rice (carbohydrate), baked salmon (protein and fat), and steamed broccoli (fiber). 

  • Person A eats their meal in this sequence: broccoli, followed by salmon, then rice, while

  • Person B flips the order — happily tucking into rice first

Assuming both individuals are free of chronic diseases, would you expect to see any significant differences in the degree to which their blood sugar levels rise from baseline? 

If your answer is “No”, you’re in for a potentially life-changing surprise. And even if you said “Yes”, you’ll still want to stay to understand how food sequencing works and, most importantly, whether it’s genuinely worth adopting to your nutrition habits. 

What is food sequencing?

Food sequencing, also known as meal sequencing or the carbohydrate-later meal pattern, refers to a specific order of eating within a meal where an individual eats:

  • Carbohydrate-free or low glycemic index (GI) foods (e.g., proteins, fats, and vegetables) before

  • Starchy or high-GI foods (e.g., white rice, fruits and potatoes)

Does the order of food you eat matter for better blood glucose control?

In the immediate sense, it appears to matter. 

Several studies have found preloading protein, fat, and fiber before carbohydrate intake to result in less pronounced postprandial (i.e., post-meal) blood glucose spikes for individuals with and without diabetes.

For example:

  • 2020 randomized controlled trial (RCT) published in Clinical Nutrition involving 16 healthy Chinese adults: In comparison with rice consumed first, followed by vegetables and meat, researchers found a significant attenuation in participants’ overall postprandial glucose response when they ate either vegetable or meat first, followed by rice (i.e., V-MR or M-VR).

  • 2018 RCT published in the Journal of Diabetes Investigation involving 15 participants with type 2 diabetes and 15 participants with normal glucose tolerance (NGT): When participants ate a protein-enriched, dietary fiber-fortified bar before their meal — which consisted of a bagel with cream cheese and orange juice — they experienced a significant decrease in postprandial glucose elevation than if they ate if after. Note: the bar contained 10.7 grams of protein and 12.7 grams of dietary fiber.

How does it work?

If the participants ate the same amount of carbohydrates, down to the grams, why is there a difference in postprandial glucose elevation? Scientists believe it comes down to two reasons:

  • Slowed gastric emptying: Protein, fat, and dietary fiber slow gastric emptying (the rate at which food exits the stomach). This, in turn, limits glucose delivery to the small intestine for absorption into the blood, resulting in gentler postprandial glucose elevation.

  • Increased glucagon-like peptide-1 (GLP-1) secretion: Fermentable (i.e., soluble) fiber, fat, and protein are known to stimulate GLP-1 secretion, promoting the release of insulin (responsible for “mopping up” the glucose in your blood) while inhibiting the release of glucagon (responsible for converting stored glycogen into glucose). Essentially, it is a potent one-two punch that helps keep glucose levels lower during the postprandial state.

What if we stretched the timeline?

OK, but as mentioned, that’s applicable in the immediate sense, i.e., mere minutes or hours after the meal. So what if we stretched the timeline to months or even years? Would food sequencing still matter for blood glucose control? 

Let’s look at this 2022, 5-year study published in Nutrients. The researchers recruited 333 patients with type 2 diabetes and divided them into two groups as follows: those who:

  1. Agreed to receive medical consultation by dietitians (Intervention group: 196 individuals)

  2. Refused to receive dietitian-led nutrition therapy (Control group: 137 patients)

The intervention group received detailed guidance on the order in which they should eat their food. 

More specifically, they were asked to eat vegetables (e.g., seaweed, mushrooms) first for five minutes, then the main dish (e.g., meat, fish, soybeans) for five minutes, and then carbohydrates (e.g., potatoes, pumpkin, corn) at the end for five minutes each meal. 

They were also recommended to:

  • Eat >120 grams of vegetables, mushrooms, and seaweed in either raw or cooked forms per meal 

  • Decrease their intake of sweetened beverages, sweets, and fruits

On the other hand, the patients in the control group received routine doctor’s consultations every one to two months, where they were simply given the vague dietary advice of “Please eat vegetables first.”

After five years, the researchers found that the intervention group experienced a significant improvement in their HbA1c (average blood sugar levels within the last three months) than those in the control group. 

Woah. Case closed — with 100% certainty, we can now say that food sequencing benefits long-term blood sugar control?

Rethinking food sequencing’s impact on blood glucose control

Not really; in truth, the study's findings warrant a healthy dose of skepticism because of a weighty limitation: the researchers did not request the dietary intake data from those in the control group. 

Meaning? It’s impossible to tell whether food sequencing or meal composition (macronutrient split, overall calorie intake) led to the observed HbA1c improvement.

While we’ve hit a dead-end there, this 2022 systematic review published in BMJ offers much-needed clarity. 

After analyzing eight trials investigating the short- (in 2-hour postprandial values) and long-term (more than two months and less than two years) effects of food sequencing on type 2 diabetes, the researchers found little to no difference in:

  • HbA1c 

  • Plasma glucose, insulin, and GLP-1 

… among those who practiced food sequencing and those who did not. 

Here’s their conclusion: Recommending meal sequencing would only be effective as part of dietary advice for type 2 diabetes.

What about weight loss?

Just because food sequencing has a negligible beneficial impact on long-term blood glucose control doesn’t mean it’s entirely without merit … right

After all, food sequencing was shown to impact the secretion of GLP-1, the exact hormone certain weight loss drugs (GLP-1 receptor agonist medications) target to suppress appetite and induce fat loss with astounding success. 

Shouldn’t that mean food sequencing could help with weight management? (Provided that you actually eat less of the carbohydrates than if you were to eat it first — because calories in vs. calories out is the ultimate determinant of weight).

Theoretically, it makes sense, but realistically, very limited evidence supports the notion. 

We have a small 2019 study published in the Journal of Diabetes and its Complications. The researchers cluster-randomized 42 individuals with type 2 diabetes into three groups:

  1. Conventional health guidance program (Conventional group)

  2. Told to adjust their energy intake to balance the total energy expenditure and encouraged to walk 

  3. Health guidance with dietary instructions focusing on meal sequence (Meal sequence group)

  4. Asked to ingest only carbohydrate-free foods (e.g., salad, meat, fish) during the first five minutes before eating carbohydrates (e.g., rice)

  5. Health guidance with dietary instructions focusing on nutritional balance (Nutritional balance group)

  6. Encouraged to increase protein intake, increase dietary fiber intake, and increase the ratio of n-3 polyunsaturated fats in total fat intake 

After six months, compared to those in the conventional group, participants in the meal sequence group experienced a greater reduction in body weight. But here’s the interesting part. Those in the nutritional balance group actually lost more weight than those in the meal sequence group. 

What does this mean for you?

Given the current scientific literature, the order in which you eat your food has little impact on your long-term blood glucose and weight management control. 

Of course, feel free to try it out if you wish; it can’t hurt. 

But a piece of advice: in the grand scheme of things, instead of tying yourself up in knots over eating your food in a particular order, your headspace, time, and energy would be better spent adopting a well-rounded approach that includes diet, exercise, and lifestyle modifications:

  • Incorporate regular monitoring: Keep track of your blood sugar levels and health status in general through periodic health screenings. This proactive approach helps you detect health issues early, which is linked to better treatment, fewer complications, and increased chances of better outcomes. 

  • Follow your diabetes treatment plan: If you have diabetes, please work closely with your healthcare team to manage your condition. Stick to the treatment plan (including dietary restrictions, medications, and physical activity goals) to control your blood glucose levels.

For those seeking more personalized diet, exercise, and lifestyle optimization guidance, why not check out the following:

  • NOVI Magnum — A holistic diabetes treatment plan that could help reduce your body weight by 5.8% and HbA1c by 0.9%

  • NOVI Optimum — A sustainable weight loss program that could help you lose 2% to 10% of your body weight