Several options can lower blood sugar, ranging from prescription medications and dietary changes to natural supplements. What works best depends on where you’re starting: someone with a new type 2 diabetes diagnosis faces different choices than someone trying to keep borderline numbers from climbing higher. Here’s what actually moves the needle, how much difference each option makes, and what to watch out for.
Prescription Medications
Metformin
Metformin remains the most commonly prescribed first-line drug for type 2 diabetes. It works three ways: it reduces the amount of glucose your liver produces, slows glucose absorption from food, and helps your cells respond better to insulin. That triple action lowers both your fasting blood sugar and the spikes that happen after meals.
Most people start at 500 mg once or twice daily, then increase gradually over several weeks to reduce stomach upset. The typical maintenance dose is 850 or 1,000 mg twice a day. An extended-release version lets you take one daily dose instead, maxing out at 2,000 mg. Digestive side effects like nausea and diarrhea are common early on but usually fade as your body adjusts.
GLP-1 Receptor Agonists
This class of medications, which includes semaglutide and liraglutide, mimics a gut hormone that triggers insulin release when blood sugar rises. They lower A1C by roughly 0.8 to 1.5 percentage points at standard diabetes doses, and they cause significant weight loss as a bonus. The 2025 American Diabetes Association guidelines specifically recommend them for people with type 2 diabetes who also have cardiovascular disease or kidney problems, because they reduce the risk of heart attacks and strokes beyond just controlling blood sugar.
SGLT2 Inhibitors
These medications work through an entirely different route: your kidneys. Normally, your kidneys reabsorb glucose back into your bloodstream. SGLT2 inhibitors block that process, so excess glucose leaves your body through urine instead. The result is lower blood sugar plus a mild drop in blood pressure (typically 2 to 10 points systolic) and lower uric acid levels. The ADA now recommends SGLT2 inhibitors for people with type 2 diabetes who have heart failure or chronic kidney disease, regardless of their A1C numbers, because the heart and kidney benefits are substantial on their own.
Dietary Changes That Lower Blood Sugar
Soluble Fiber
Soluble fiber slows the rate at which sugar enters your bloodstream after a meal. A meta-analysis of randomized controlled trials found that roughly 7.5 to 8.5 grams of supplemental soluble fiber per day significantly improved blood sugar control in people with type 2 diabetes. You can hit that target through food (oats, beans, lentils, barley, flaxseed, apples) or through a fiber supplement like psyllium husk. Spreading your fiber intake across meals gives you the most consistent effect on post-meal glucose spikes.
Apple Cider Vinegar
Apple cider vinegar has modest but real effects on blood sugar. In an eight-week randomized trial, people with type 2 diabetes who consumed about two tablespoons (30 ml) daily saw significant drops in fasting blood sugar and A1C compared to a control group. Their LDL cholesterol and total cholesterol also improved. The acetic acid in vinegar appears to slow stomach emptying and improve insulin sensitivity. Diluting it in water before meals is the standard approach, since undiluted vinegar can damage tooth enamel and irritate your throat.
Supplements With Clinical Evidence
Berberine
Berberine is the supplement with the strongest head-to-head data against a prescription drug. In a three-month clinical trial, people with newly diagnosed type 2 diabetes took either berberine or metformin at 500 mg three times daily. The results were nearly identical: berberine lowered A1C from 9.5% to 7.5%, while metformin lowered it from 9.2% to 7.7%. Fasting blood sugar dropped comparably in both groups. Berberine actually outperformed metformin on one front: triglycerides and total cholesterol dropped significantly more in the berberine group.
That said, this was a small study (36 people), and berberine isn’t regulated with the same rigor as prescription medications. The quality and potency of supplements vary between brands. It can also cause digestive side effects similar to metformin, including cramping and diarrhea, and it interacts with several common medications by affecting how your liver processes them.
Magnesium
Magnesium deficiency is surprisingly common in people with type 2 diabetes, affecting somewhere between 14% and 48% depending on the population studied. That matters because magnesium plays a direct role in how your cells respond to insulin. When levels are low, insulin resistance gets worse, creating a cycle where high blood sugar depletes magnesium further. Clinical studies show that oral magnesium supplementation reduces insulin resistance and improves insulin sensitivity in both diabetic and overweight nondiabetic people. Good food sources include dark leafy greens, nuts, seeds, and legumes. If you supplement, magnesium glycinate and magnesium citrate are better absorbed than magnesium oxide.
Cinnamon
Cinnamon has shown modest blood sugar-lowering effects in some studies, but which type you use matters enormously. Cassia cinnamon, the variety sold in most grocery stores, contains up to 1% coumarin, a compound linked to liver damage in animal studies. Ceylon cinnamon contains only a trace amount of coumarin (about 0.004%), making it roughly 250 times lower in this compound. If you plan to use cinnamon regularly for blood sugar, Ceylon is the safer long-term choice. Heavy daily consumption of cassia cinnamon can push you past the tolerable daily intake for coumarin relatively quickly.
How These Options Compare
Prescription medications deliver the largest, most reliable reductions in blood sugar. GLP-1 receptor agonists can drop A1C by up to 1.5 percentage points, and metformin has decades of safety data behind it. For people with cardiovascular or kidney complications, the newer drug classes offer benefits that go well beyond glucose control.
Supplements and dietary strategies produce smaller effects, but they can be meaningful, especially in combination. Berberine showed metformin-level results in a clinical trial. Soluble fiber and apple cider vinegar won’t replace medication for someone with an A1C of 9%, but for someone with prediabetes or mildly elevated blood sugar, they can be enough to shift numbers back into a healthy range alongside other lifestyle changes like regular walking and reducing refined carbohydrates.
Risks of Lowering Blood Sugar Too Much
Hypoglycemia, when blood sugar drops too low, is the main risk of aggressively lowering glucose. Symptoms include shakiness, sweating, confusion, rapid heartbeat, and in severe cases, loss of consciousness. Certain drug combinations increase this risk significantly. Research has identified that combining some diabetes medications with common drugs like certain blood pressure medications, the antibiotic cotrimoxazole, acetaminophen (Tylenol), or the acid reflux drug pantoprazole can more than double the rate of hypoglycemic episodes.
Insulin and sulfonylureas carry the highest standalone hypoglycemia risk among diabetes drugs. Metformin, GLP-1 receptor agonists, and SGLT2 inhibitors rarely cause low blood sugar on their own. If you’re stacking multiple blood sugar-lowering approaches, whether prescriptions, supplements, or both, the combined effect can push glucose lower than any single one would. Monitoring your blood sugar more frequently when adding a new supplement or medication helps you catch drops before they become dangerous.