Do you wind down at night by doom-scrolling on the couch with a glass of wine? Do you stay up way too late or eat a large dinner before bed? These seemingly harmless evening habits could be sabotaging your blood sugar more than you realize.

Research shows that your internal clock affects how well you metabolize sugar.1

Speksnijder EM, Bisschop PH, Siegelaar SE, Stenvers DJ, Kalsbeek A. Circadian desynchrony and glucose metabolism. J Pineal Res. 2024;76(4):e12956. doi:10.1111/jpi.12956

As bedtime approaches, your body produces less insulin and becomes less sensitive to it. In other words, your body handles glucose more efficiently in the morning than at night.2 Many factors can affect your blood sugar, especially in the evening, so we asked dietitians to share the six habits you should avoid after 5 p.m. for better blood sugar control.

1. Eating Large Meals or High-Carb Snacks

One of the most disruptive evening habits for your blood sugar is consuming large meals or high-carb snacks within a few hours of bedtime. Because your body doesn’t handle glucose in the evening as well as it does in the morning, a large meal or a high-carb snack can be a lot for it to process, literally.2 “Refined carbohydrates, such as white bread, pasta, pastries, sugary snacks and sugar-sweetened beverages are most problematic after 5 p.m. because they are digested quickly, causing rapid blood sugar spikes that the body is less able to manage in the evening,” says Michelle Routhenstein, M.S., RD, CDCES, CDN, a certified diabetes educator.2

2. Drinking Alcohol in the Evening

While a cocktail with dinner might seem harmless, alcohol consumption after 5 p.m. can significantly disrupt your blood sugar throughout the night and into the next morning. “Alcohol can initially lower blood sugar but often leads to rebound hyperglycemia overnight and disrupts sleep, further impairing blood sugar control,” says Routhenstein. This is especially true if you’re taking medications to help with your blood sugar, or if the drink is high in sugar, like a mixed cocktail.3

The problem stems from your liver’s dual responsibilities. When the liver is busy breaking down alcohol, it prioritizes this process and may not release sufficient glucose to keep blood sugar levels stable. This creates unpredictable fluctuations that can persist through the night.34

3. Not Getting Adequate Sleep

Your sleep schedule plays a crucial role in blood sugar regulation, and staying up too late or having inconsistent bedtimes can wreak havoc on your glucose control. Studies show that sleep deprivation can impair glucose tolerance and insulin sensitivity. Even just one night of inadequate sleep can make your body use insulin less effectively, setting you up for worse glucose control the following day.5

The combination of poor sleep and glucose instability creates a vicious cycle. When you don’t get enough quality sleep, your body produces more stress hormones like cortisol, which can raise blood sugar levels. Additionally, sleep deprivation can increase hunger hormones, making you more likely to crave high-carbohydrate foods the next day.5

4. Not Staying Hydrated

Failing to maintain proper hydration in the evening hours can negatively impact your blood sugar control overnight. “When you’re dehydrated, the glucose in your bloodstream becomes more concentrated, leading to higher blood sugar levels,” says Alyssa Pacheco, RD, the PCOS Nutritionist. “By staying hydrated, you can keep blood sugar levels more stable. Dehydration can also impair insulin sensitivity, leading to higher blood sugar levels.”6

However, the timing of hydration matters. While it’s important to stay hydrated, drinking large amounts of fluids right before bed can disrupt your sleep by causing frequent trips to the bathroom.

5. Staying Sedentary All Evening

Remaining inactive throughout the evening hours can significantly impair your body’s ability to regulate blood sugar overnight and into the next day. “Taking a short walk, even 5 to 10 minutes, within 60 to 90 minutes after eating a meal or snack can significantly improve insulin sensitivity and lower blood sugar levels, shares Pacheco. “If you do not have the space to go for a walk, exercising in place (such as squats) can substitute for walking.” Even gentle evening activities like stretching, doing household chores or taking a brief walk around your home can help improve glucose uptake by your muscles and support better blood sugar control overnight.7

6. Skipping Your Wind-Down Routine

When you don’t take time to wind down in the evening, your stress hormone levels can remain elevated. High cortisol levels can raise blood sugar and make your body less responsive to insulin. This creates a cycle where poor evening habits lead to elevated stress, which then disrupts blood sugar control.8

Simple evening activities like reading, gentle stretching, meditation or taking a warm bath can help lower stress hormones and support better glucose regulation. “People often think of food when it comes to blood sugar regulation, but your stress levels and your sleep quality actually play a big role here too,” Pacheco says. “When you have a regular evening routine, it can help reduce stress and ensure more restful sleep. This can lead to better cortisol regulation and lower blood sugar levels the following day.”

Our Expert Take

As evening approaches, your body makes less insulin and becomes more resistant to it. This means you can’t metabolize glucose as well at night as you do in the morning. Many factors like diet, stress, exercise and alcohol consumption can affect our blood sugar. Understanding what habits to avoid after 5 p.m. can help you maintain better glucose control overnight and leave you feeling more energized in the morning. (Eating well)