Time to Eat? Why Timing Matters for People With Diabetes
By Alexandra Frost
Do people with diabetes need to eat at regular intervals? Is late night snacking ok? What about intermittent fasting? Learn more about why timing matters when eating if you have diabetes.
There is no easy answer to the question: “How many times should I eat in a day?”
Advice on when it’s best to eat can be confusing for a person without diabetes (should you eat three square meals a day, or six small meals per day? What about only eating when you’re hungry?). Add in the element of diabetes, and what is considered healthy guidance for many could become dangerous advice to people with diabetes.
How an individual with diabetes should time their meals will vary and depend on their body’s needs, their blood glucose patterns, the type of medication they’re taking, and other factors.
“It has to be an individualized approach,” said Dr. Henry Anhalt, pediatric endocrinologist and chief medical officer at Embecta, a diabetes supply company.
“Depending on the person’s age, their stage in life, their occupation, their living situation, their work hours, their medication, and so on,” Anhalt said. “All of those will impact how a person should best optimize their nutrition [and timing].”
Even if someone doses insulin in the same place at the same time each day, Anhalt points out that there can be a 20-30% variation in insulin absorption. Considerations like these, and the fact that our lives and our bodies are far from robotic, mean there is no real one-size-fits-all answer to the question about meal timing.
Here’s what to consider, as you attempt to answer the question for yourself with the hands-on involvement of your care team.
Do People With Diabetes Need to Eat at Regular Intervals?
If your circumstances enable you to eat regularly and you have consistent access to food, then Mariana Dineen, a registered dietitian based in Chicago and the founder of Elemento Health, recommends following regular eating patterns. In her treatment of patients with diabetes, she’s found that many different types of diabetes medications require certain meal requirements.
“Skipping meals and lack of meal structure can throw off the balance between food intake and medication and this can result in poorly controlled blood glucose,” she said. “Eating at regular intervals also ensures that carbohydrates are spaced evenly throughout the day, which translates to better blood glucose control.”
Skipping a Meal: A Disaster For People With Diabetes?
Dineen’s recommendation aside, those living with diabetes know that real life does throw curveball, like major traffic jams, long work shifts without access to food, and other complications, so eating at regular intervals every day might not always be possible. And that’s okay.
“I don't like to add stress by suggesting that people with diabetes must eat at regular intervals. Life is busy and sometimes unpredictable, and so it is not always possible to eat at the same times,” Dr. Sarah Musleh, Dallas-based endocrinologist and cofounder at Anzara Health, said. “In theory, if your basal insulin dose is right for you and if your blood sugars are within a safe range, you should be able to skip or delay a meal and be safe.”
Late-Night Snacking: Is It OK If You Have Diabetes?
The topic of nighttime eating can be complicated, and like other eating questions, depends on a multitude of factors.
Anhalt said that it’s not so much a concern of what will happen overnight, but rather the lack of information people have about nighttime blood sugars. After all, it’s not likely you are waking up hourly to ensure your blood sugars are in check. For many, nighttime accounts for 30% of the time in range, Anhalt adds, and can be tracked by wearing a continuous glucose monitor (CGM) sensor, which he calls “critical” to obtaining essential data on what your blood sugars are doing at night, with or without a snack.
In a 2022 review of 16 studies, researchers concluded that there was no consistent relationship between having a bedtime snack and improving blood sugar control.
If you do plan to eat before bed, Musleh recommends avoiding high-carbohydrate snacks at that time. “Going to bed with good blood sugar levels and being able to maintain that overnight sets you up for a better morning and next day,” she said.
One might ask why it really matters if you are going to be asleep, but Musleh adds that high overnight blood sugars can cause poor sleep, and waking up with high blood sugars is a less-than-ideal way to start the day.
The Bottom Line
Overall, experts pointed to the importance of being able to eat on a schedule that works best for you and is most convenient for your life, provided you’ve worked with your healthcare provider to help you achieve desirable results. If you can eat regularly and predictably, it might be easier to control your blood sugar in some circumstances. If you can’t, then communicate with your provider about how to adapt your eating timing for the best outcomes.
Time-restricted eating and Intermittent fasting: The do’s and don’ts for people with diabetes
The polar opposite of eating at regular intervals is intermittent fasting or time-restricted eating. If you have prediabetes or are hoping to manage diabetes through weight loss, this might be something you’ve considered.
“Intermittent fasting (IF), although not new, has recently gained attention and popularity as a means to facilitate weight loss and improve metabolic health,” Dineen said.
There are two basic versions for a “time-restricted” eating schedule:
The most common is 16/8, meaning eating in an 8-hour window, and not for the 16 hours following that.
Also common is the 5/2 schedule, meaning eating normally 5 days per week, and restricting caloric intake to 500-600 calories on the remaining 2 days.
Dineen noted that research has proven IF to have similar outcomes in weight loss as daily calorie restriction. In addition, she said, “Studies on the safety and benefits of IF with diabetes are limited, but a few have shown that IF could be a good tool and non-medical treatment of diabetes.”
For example, a 2019 review concluded that IF was helpful in weight loss for both Type 1 and Type 2 diabetes, but also warned of potential immediate risks of hypoglycemia, which should always take precedence over potential long-term health benefits.
“Intermittent fasting per se isn’t a challenge, provided that the mechanism of action of the drugs that you’re taking permits you to be for hours without food,” Anhalt said. “I don’t see how intermittent fasting is any worse than any other diet, or any better than any other diet.
Anhalt added that if someone doesn’t have an insulin pump or hasn't adjusted their insulin for intermittent fasting, then they’re putting themselves at risk of high or low blood sugars. Otherwise, he doesn’t see any issues with intermittent fasting or time-restricted eating. “Less food, less insulin, less glucose, less fat, less medication required,” he said.
All of our experts agreed that changes in the timing of your food intake must be something you discuss with your diabetes care team before trying to make those changes.
“Special attention should be paid to medication adjustment, frequency of glucose monitoring and fluid intake,” Dineen said, adding it’s not safe if you are pregnant or lactating, or for young children and the elderly, especially if they have diabetes.
Overall, the experts pointed to the potential to be able to eat on a schedule that works best for you and is most convenient for your life, provided that you’ve talked with your health care provider.