The fastest way to raise low blood sugar is to eat or drink 15 grams of simple carbohydrates, then wait 15 minutes and recheck how you feel. This approach, known as the 15-15 rule, is the standard method for treating a blood sugar drop. What you choose matters, though. Some foods work in minutes while others take much longer to move glucose into your bloodstream.
How to Know Your Blood Sugar Is Low
Blood sugar typically needs to fall below about 70 mg/dL before symptoms appear, though individual thresholds vary. The early signs are hard to miss once you know what to look for: shakiness, sweating, a sudden wave of hunger, dizziness, and difficulty concentrating. You might also notice a fast heartbeat, irritability, or tingling in your lips or tongue.
If blood sugar continues dropping, symptoms escalate to confusion, slurred speech, blurry vision, and loss of coordination. Severe lows can cause seizures or loss of consciousness. The goal is to catch it early and eat something fast-acting before it gets to that point.
Fast-Acting Foods That Work in Minutes
When your blood sugar is low, you want pure, simple carbohydrates with no fat, fiber, or protein slowing them down. Liquids tend to raise blood sugar slightly faster than solids because they empty from the stomach more quickly. Here are reliable options, each providing roughly 15 grams of carbohydrates:
- 4 ounces (half a cup) of fruit juice: Orange or apple juice works well. Skip “no sugar added” varieties in this situation.
- 4 ounces of regular soda: Not diet. The sugar hits your bloodstream fast.
- Glucose tablets: Sold at any pharmacy. They’re pre-measured so you don’t have to guess portions.
- 1 tablespoon of honey or sugar: Dissolved in water if possible, for faster absorption.
- Hard candies: About 3 to 4 pieces, depending on the brand. Check the label for 15 grams of sugar.
- A few spoonfuls of raisins: Around 2 tablespoons.
A serving of white rice or white bread also spikes blood sugar almost as dramatically as pure table sugar, but these take longer to chew and digest, so they’re not ideal in an urgent moment. Save them for the follow-up step.
What Not to Eat During a Low
Your instinct when you feel shaky and hungry might be to grab a candy bar or a handful of peanut butter crackers. This is actually counterproductive. Fat slows down the digestive process significantly, delaying the rise in blood sugar when you need it most. Research published in The American Journal of Clinical Nutrition found that adding fat to a carbohydrate meal reduced and delayed the glucose response, likely because fat inhibits how quickly the stomach empties its contents.
Chocolate, ice cream, cookies, and peanut butter all contain enough fat to blunt the speed of sugar absorption. Protein has a similar slowing effect. These foods will eventually raise blood sugar, but “eventually” is the problem when you’re dizzy and struggling to concentrate. Stick with simple carbohydrates that contain little else.
The Follow-Up Snack That Prevents a Second Drop
Here’s what many people miss: after treating the initial low with fast-acting sugar, you need a second snack to keep your blood sugar stable. The quick carbohydrates you just ate will spike your glucose, but that spike fades. Without a follow-up, your blood sugar can dip right back down.
This is where the combination of complex carbohydrates, protein, and a small amount of fat becomes useful. Fiber, protein, and fat all slow the digestion of carbohydrates and create a longer, more gradual release of glucose into the blood. Good follow-up snacks include half a sandwich with meat or cheese, crackers with peanut butter, a small handful of nuts with a piece of fruit, or yogurt with granola. The Joslin Diabetes Center recommends pairing carbohydrates with protein or fat specifically to prevent this rebound drop.
Wait about 15 to 30 minutes after your initial treatment before eating the follow-up snack. If you still feel symptomatic after the first 15 minutes, repeat another 15 grams of simple carbohydrates before moving on to the stabilizing snack.
Why Timing and Portions Matter
Overtreating a low is one of the most common mistakes. When you feel shaky and anxious, the urge is to eat everything in sight until the feeling stops. But symptoms lag behind your actual blood sugar level by several minutes. If you keep eating past 15 grams, you can end up swinging too high, which creates its own problems, especially if you manage diabetes with insulin.
The 15-minute waiting period exists because that’s roughly how long it takes for simple carbohydrates to move from your stomach into your bloodstream and start raising glucose levels. Eating more during that window doesn’t speed things up. It just means more sugar is in the pipeline, and you’ll likely overshoot.
If you use a glucose meter, check your reading after 15 minutes. If it’s still below 70 mg/dL, eat another 15 grams and wait again. Once you’re above 70, move on to your follow-up snack to hold steady.
Foods That Raise Blood Sugar Gradually
Not everyone searching for this information is in the middle of an emergency. If your blood sugar tends to run low between meals or you want to prevent dips throughout the day, focus on foods with a high glycemic index paired with something that extends their effect. White bread, bagels, rice cakes, most packaged breakfast cereals, crackers, and white rice all produce a rapid glucose response. These rank 70 or higher on the glycemic index, meaning they raise blood sugar almost as fast as pure glucose.
For day-to-day management, eating these high-glycemic foods alongside protein or healthy fats gives you both a prompt rise and lasting stability. A bagel with cream cheese, rice with chicken, or cereal with milk all deliver glucose relatively quickly while providing the sustained energy that prevents another dip an hour later. Eating smaller, more frequent meals that include carbohydrates at each sitting also helps keep blood sugar from falling between meals.