Should You Cut Off Sugar After 8 p.m.? Dietitians Weigh In

Should You Cut Off Sugar After 8 p.m.? Dietitians Weigh In

  • Eating lots of added sugar at night can make it harder to fall and stay asleep.
  • Blood sugar spikes before bed can mess with hormones that help your body get sleepy.
  • Choose snacks with protein, fiber and healthy fats to keep blood sugar steady for better sleep.

Most Americans already consume too much added sugar—to the tune of about 17 teaspoons per day—which is linked to higher risks of heart disease, type 2 diabetes and poor sleep. When foods high in added sugar are eaten close to bedtime, they can cause blood sugar spikes and crashes, making it harder to fall and stay asleep. Not all sugar is created equal, though. “Naturally-occurring sugars are found in whole foods that also provide fiber, vitamins and minerals, while added sugars are often found in more refined, ultra-processed foods,” says Val Warner, M.S., RD, CSSD, CPT. “Consuming too much added sugar is what’s linked to negative health outcomes.”

To understand how eating sugar in the evening affects sleep—and what to reach for instead—we spoke with registered dietitians to break down the science and share practical tips.

How Sugar Can Impact Your Sleep

When you eat foods high in added sugar—like candy or baked goods—your blood sugar rises and your body releases insulin to move that glucose into your cells for energy. That process is completely normal. But when blood sugar rises sharply, particularly in the evening, it can throw off the delicate balance of hormones that help regulate your sleep-wake cycle.

“High amounts of added sugar can cause a rapid spike in blood glucose, triggering the release of insulin to bring levels back down,” explains Warner. If levels drop quickly afterward, your body may release hormones like cortisol and adrenaline to bring them back up—leaving you feeling alert when you’d rather be asleep. “When cortisol stays high at night, it can delay the natural rise in melatonin that signals your body it’s time to sleep,” says Lisa Young, Ph.D., RDN. This mismatch between cortisol and melatonin can make it more difficult to relax and fall asleep.

These blood-sugar fluctuations can also affect how deeply and how long you sleep. Studies show that diets high in added sugar are linked to shorter sleep duration and more frequent nighttime awakenings. Rapid rises and dips in glucose may also disrupt REM sleep—the stage that supports memory, learning and emotional regulation—and reduce time spent in deep, restorative sleep. That’s why your evening sweet tooth can sometimes lead to a night of tossing and turning.

Should 8 p.m. Be the “Cutoff Time” for Added Sugar? 

While there’s nothing magical about the clock striking 8 p.m., the timing of your last meal or snack can influence how your body handles sugar—and how well you sleep afterward. Our metabolism follows a circadian rhythm, meaning that we process and use energy differently at different times of day.

“Timing matters when it comes to thinking about your sugar intake,” says Jenny Finke, M.S., RDN. As the day winds down, digestion slows and insulin sensitivity decreases, making it harder for the body to manage large amounts of sugar. “Ideally, the last meal of the day is eaten 2 to 3 hours before bed, as this allows time for digestion and processing of the sugars or carbohydrates present in the meal,” Finke adds. “This spacing supports steadier blood sugar as melatonin levels rise, and it helps support optimal sleep quality,” she adds. 

That said, there’s no one-size-fits-all “sugar curfew.” The key is to tune in to your body’s cues—if you tend to feel wired or wake frequently after a nighttime dessert, it may help to enjoy it earlier in the day.

What Dietitians Say to Eat Instead

If you’re truly hungry before bed, skipping food altogether isn’t the answer—going to sleep hungry can make it harder to drift off and stay asleep. Instead, Warner recommends a snack that combines protein, healthy fats, fiber and complex carbohydrates to help keep blood sugar steady. This balance helps slow digestion and prevents the sharp rises and dips that can interfere with deep, restorative sleep.

Fenke recommends our Nut & Berry Parfait for a mix of protein, fiber and healthy fats. She suggests swapping the berries for frozen tart cherries, as they are associated with improved sleep quality and duration.

Dietitians also recommend our Chia Seed Pudding as a fiber- and protein-rich option that can help keep blood sugar steady and support better sleep. Chia seeds also provide magnesium and calcium, nutrients that play a role in converting tryptophan to serotonin, a precursor to melatonin. Make it with dairy or calcium-fortified milk, then top with fruit and nuts for a balanced combination of carbs, healthy fats and sleep-supporting nutrients.

Ultimately, it’s less about cutting out sweets entirely and more about how you enjoy them. “It’s all about pairing the right foods, not about restriction,” Warner encourages.

Our Expert Take

You don’t have to avoid dessert altogether for better sleep. Thankfully, it’s less about cutting out sweets entirely and more about how you enjoy them. If you want something sweet before bed, opt for foods that contain naturally-occurring sugars and enjoy them with foods that contain fiber, protein and healthy fats. Balanced snacks that support stable blood sugar also help you sleep better.