The fastest way to raise glucose levels is to eat 15 grams of fast-acting carbohydrates, wait 15 minutes, then recheck your blood sugar. This approach, known as the 15-15 rule, is the standard method for treating a blood sugar drop. But the best strategy depends on how low your glucose is, why it dropped, and whether this is a one-time event or a recurring pattern.
Recognizing Low Blood Sugar
Blood sugar below 70 mg/dL is considered low. At that level you may feel shaky, sweaty, dizzy, or unusually hungry. Your heart might race, and you could have trouble concentrating or feel tingling in your lips or tongue. These are your body’s early warning signals, driven by stress hormones trying to push glucose back up on their own.
If blood sugar drops below 54 mg/dL, the brain starts running short on fuel. Symptoms shift from uncomfortable to dangerous: confusion, slurred speech, blurry vision, loss of coordination, and muscle weakness. At the most severe stage, a person may have seizures, lose consciousness, or be unable to eat or drink without help. Some people, particularly those who experience frequent lows, lose the ability to feel these warning signs altogether. This is called hypoglycemia unawareness, and it makes regular monitoring especially important.
The 15-15 Rule for a Quick Fix
When your blood sugar is low but you’re still alert and able to swallow, eat or drink 15 grams of fast-acting carbohydrates. Then wait about 15 minutes for the sugar to reach your bloodstream and retest. If you’re still below 70 mg/dL, repeat with another 15 grams. Once your levels stabilize, eat a small meal or snack that includes protein and fat to keep them steady.
The goal is a controlled rise, not a spike. Eating too much sugar at once can send your glucose soaring, which triggers a crash later. Fifteen grams is a precise, moderate dose that nudges levels back into a safe range without overcorrecting.
Best Foods for Raising Glucose Fast
Not all carbohydrates hit your bloodstream at the same speed. You want simple, fast-digesting sources with little fat or fiber to slow them down. Good options that deliver roughly 15 grams of fast-acting carbohydrates include:
- Glucose tablets: 3 to 4 tablets, depending on the brand. These are the most precise option because each tablet contains a known amount.
- Fruit juice: About 4 ounces (half a cup) of orange or apple juice.
- Regular soda: About 4 ounces of non-diet soda.
- Hard candy: A small handful, such as 5 to 6 Lifesavers.
- Honey or table sugar: About 1 tablespoon.
White bread, rice cakes, crackers, and bagels also rank very high on the glycemic index. A serving of white rice has nearly the same blood sugar impact as eating pure table sugar. These work in a pinch, but liquids and glucose tablets tend to act faster because they require less digestion.
Avoid reaching for chocolate, ice cream, or peanut butter crackers. The fat in these foods slows absorption, which is the opposite of what you need in the moment.
When Someone Can’t Treat Themselves
If a person is too confused, unconscious, or having a seizure, they cannot safely swallow food or liquid. This is when emergency glucagon becomes critical. Glucagon is a hormone that signals the liver to release its stored glucose into the bloodstream, raising levels within minutes.
Emergency glucagon comes in two forms. The traditional option is an injectable kit containing a vial of powdered glucagon and a syringe of saline that must be mixed before injection. The newer option is a nasal spray that delivers glucagon through the lining of the nose with no mixing or needles required. The nasal spray is simpler for bystanders who may be untrained or panicked. If someone in your household is at risk for severe lows, keeping one of these kits accessible and making sure family members know how to use it can be lifesaving.
How Your Body Raises Glucose on Its Own
Your liver acts as a glucose warehouse. After meals, it stores excess sugar in a compact form called glycogen. When blood sugar drops between meals or overnight, the pancreas releases glucagon, which tells the liver to convert that glycogen back into glucose and send it into the bloodstream. This process is your body’s built-in safety net.
The system works well in most people, but it can fail in certain situations. In people with diabetes, medications like insulin can overpower the liver’s ability to keep up. Prolonged fasting, heavy alcohol use, or liver disease can also deplete glycogen stores, leaving the liver with less glucose to release when it’s needed.
Preventing Drops During Exercise
Physical activity pulls glucose out of the bloodstream to fuel working muscles, and blood sugar can drop during or after a workout. Research on endurance athletes found that even a very small amount of carbohydrate during exercise, roughly 10 grams per hour, was enough to eliminate exercise-induced low blood sugar and improve endurance by 22%.
For practical purposes, this means having a small snack before or during prolonged activity can make a significant difference. A few sips of a sports drink, half a banana, or a small handful of dried fruit every 20 to 30 minutes during extended exercise helps keep glucose stable. If you take insulin or diabetes medication, checking your blood sugar before, during, and after workouts helps you learn your body’s patterns and adjust your food or medication timing accordingly.
Long-Term Strategies for Reactive Hypoglycemia
Some people experience blood sugar drops a few hours after eating, even without diabetes. This is called reactive hypoglycemia, and it typically happens when the body overproduces insulin in response to a meal heavy in simple carbohydrates. The glucose spikes quickly, insulin overshoots, and blood sugar crashes.
The fix is mostly dietary. Eating smaller meals or snacks every two to four hours keeps glucose delivery steady rather than dumping it all at once. The composition of those meals matters just as much as the timing. Pairing complex carbohydrates with protein and healthy fat slows digestion and flattens the glucose curve, preventing the spike-and-crash cycle.
Good complex carbohydrate choices include brown rice, quinoa, oatmeal, sweet potatoes with the skin, barley, and legumes like beans and lentils. Pair them with protein sources like eggs, Greek yogurt, lean meat, fish, nuts, or tofu. Cook with olive oil, avocado oil, or other plant-based fats. Meanwhile, minimize white rice, white bread, pastries, candy, sweetened drinks, and other simple carbohydrates that your body converts to sugar almost immediately.
Using a Continuous Glucose Monitor
A continuous glucose monitor (CGM) is a small sensor worn on the skin that tracks blood sugar in real time and can alert you before levels drop too low. Most devices allow you to set a custom low-glucose alarm. The average threshold people use is around 74 mg/dL, but the range varies from 60 to 100 mg/dL depending on individual needs. Setting the alarm a bit higher gives you more lead time to eat something before symptoms start, and studies show that higher alarm thresholds correlate with less total time spent in hypoglycemia.
CGMs are especially valuable for people with hypoglycemia unawareness, since the device catches drops that the body no longer signals on its own. Even for people without diabetes who experience reactive lows, wearing a CGM temporarily can reveal which meals and patterns trigger crashes, making it easier to adjust your diet with real data rather than guesswork.