If you have type 2 diabetes and are feeling confused, tired, and like you just can’t get your mind to work right, you’re not alone. This condition is called brain fog, and it can be part of diabetes. In fact, the link between diabetes and brain fog has been known about for more than 100 years. Fortunately, there are ways to prevent brain fog and to improve it if you’ve developed it.

Brain Fog Symptoms

Brain fog, also known as mental fog, can make your brain feel like it’s running in slow motion. People with brain fog experience symptoms such as:

• General forgetfulness
• Loss of train of thought
• Confusion
• Difficulty focusing and concentrating
• Slow reaction time
• Fatigue

DiabetesTeam members report experiencing symptoms of brain fog. “I’m still sleepy. I’m like this every morning, even after coffee,” one DiabetesTeam member said.

Another said, “The memory, she don’t work as before. Needed to ask about when to take medication. Am good now!”

How Diabetes Causes Brain Fog

The brain actually is the organ that uses the most energy in the body. Changes in blood glucose (blood sugar) levels can affect the nerves and blood vessels in the brain and cause changes in brain function. These changes can make you tired, forgetful, and confused.

Hyperglycemia (high blood sugar) is common when diabetes isn’t well controlled. Over time, too much sugar can hurt blood vessels in the brain. These blood vessels help bring oxygen to your brain cells. Over time, these brain cells don’t get enough oxygen and die. The symptoms of hyperglycemia can be hard to detect, so you might not notice the effects until damage has been done.

People with diabetes also often experience hypoglycemia (low blood sugar). If you have type 2 diabetes and are taking medications called meglitinide or sulfonylurea (and even insulin), you’re especially at risk for low blood sugar. Like with high blood sugar, low blood sugar also affects your body’s ability to get oxygen to your brain. Unlike symptoms of high blood sugar, the effects of low blood sugar — dizziness, irritability, trouble walking or talking, and even fainting — are hard to ignore. These dips in sugar can also have longer-term emotional effects, like worsening memory and attention span.

Causes of Brain Fog

Type 2 diabetes can cause lots of other conditions that can make you feel tired and foggy. These include:

• Heart disease
• Anemia
• Thyroid and adrenal problems
• Kidney disease
• Liver problems

A lack of sleep can also cause brain fog. However, many people with type 2 diabetes have trouble with falling and staying asleep. Many DiabetesTeam members report poor sleep. “I am very dizzy and tired. I didn’t get much sleep last night,” one said.

Almost a quarter of people with type 2 diabetes have obstructive sleep apnea, a condition in which the airways are blocked during sleep, and more than half of people with type 2 diabetes have some sort of problem with breathing while they’re sleeping.

Nerve pain from diabetes can tire you out, as DiabetesTeam members have experienced. “My right foot and ankle are acting up from the neuropathy, and I didn’t sleep much,” one said.

In addition, mental health conditions related to diabetes, like stress, anxiety, and depression, can also cause brain fog symptoms. “Any stress can raise your numbers,” a DiabetesTeam member shared. “Anxiety is a major stressor.”

Avoiding Brain Fog

Keeping your diabetes well managed may help reduce brain fog or improve brain fog symptoms. Maintaining steady glucose levels can support healthy brain function. Monitoring your blood sugar, getting regular exercise, and improving sleep are three ways that may help reduce brain fog.

Monitoring Blood Sugar Levels

If you use insulin, properly monitoring your blood sugar levels throughout the day may help you better control your type 2 diabetes. There are two different types of monitoring methods: continuous glucose monitors (CGMs) and blood sugar meters.

CGMs are worn throughout the day and measure your blood glucose levels using a sensor. Blood sugar meters use strips to detect levels of sugar in small amounts of blood. You may have to take readings with blood sugar meters several times a day to detect dangerous highs and lows.

To make sure that you’re getting accurate readings from a blood sugar meter, check that your device is properly calibrated and that your test strips are not expired and kept in the right conditions (not too hot, cold, or humid). Before taking a blood sample, wash your hands with warm water. Use the sides of your fingertips for the best blood test results.

Getting Exercise

Exercise is a good way to cut through brain fog. Physical activity improves blood flow, including to your brain. Aim for an hour and a half of moderate aerobic activity, such as walking, per week.

Exercise is especially important for people with type 2 diabetes because it can help improve their blood sugar levels. You don’t need to start with a complicated workout. The American Diabetes Association says that even a half hour of walking a day can improve symptoms of diabetes, including brain fog. If you don’t have time for a half-hour walk at once, you can break up your strolls for several short walks a day.

For people who have stability problems, assistive devices can help get the effects of walking. “I never heard of a walk pad, but just purchased one,” a DiabetesTeam member reported. (A walk pad is a compact treadmill designed for slow indoor walking.) “I love to walk, but am quite unsteady in my gait and afraid of stumbling and falling out walking. Now I’ll be able to stay walking and not have to worry as much.”

Getting a Good Night’s Sleep

Uninterrupted, quality sleep helps support brain health and may reduce brain fog. It has also been shown to improve blood sugar levels. If you have untreated obstructive sleep apnea, you could be missing out on treatments that may improve your sleep, such as continuous positive airway pressure (CPAP) therapy, which uses a machine to keep your airway open while you sleep. If you think you might have sleep apnea, talk to your healthcare provider about getting a sleep study and whether a CPAP machine might help.

Small improvements in sleep hygiene are also helpful in getting a better night’s sleep and helping with brain fog. Keeping a set schedule, avoiding screens for an hour before bedtime, and avoiding drinks and snacks before bed can make it more likely that you’ll enjoy a good night’s sleep and wake up refreshed.

Join the Conversation

On DiabetesTeam, people share their experiences with type 2 diabetes, get advice, and find support from others who understand.

Have you experienced diabetes-related brain fog? How have you treated your brain fog? Let others know in the comments below.