Water is the single best thing to drink on an empty stomach. It rehydrates you after hours of sleep, kickstarts digestion, and even temporarily raises your metabolic rate. But beyond plain water, several other drinks offer real benefits when consumed before eating, and a few popular ones are better saved for later.
Why Water Comes First
After six to eight hours of sleep, your body is mildly dehydrated. Drinking water before anything else replenishes fluid levels and gets your digestive system moving. But the benefits go further than simple rehydration. Drinking about 500 ml (roughly two cups) of water has been shown to increase metabolic rate by up to 30%. That boost kicks in within 10 minutes, peaks around 30 to 40 minutes later, and lasts for over an hour. In overweight children, even a modest amount of cold water raised resting energy expenditure by 25% for over 40 minutes.
Room temperature or slightly warm water tends to feel more comfortable on an empty stomach. Cold water works fine too, and the slight metabolic edge from cold water is real, though small. The important thing is simply drinking it before you reach for coffee or food.
Lemon Water for a Gentle Start
Squeezing half a lemon into warm water is one of the most popular empty stomach drinks, and there’s modest science behind it. The citric acid in lemon juice appears to increase bile acid secretion from the gallbladder into the small intestine. Bile acids help with gut motility and the absorption of fats and fat-soluble vitamins, which matters once you do eat. That said, the direct effect on digestion hasn’t been fully quantified in human trials.
Lemon water also provides a small dose of vitamin C and makes plain water more appealing if you struggle to drink enough in the morning. If you drink it regularly, consider using a straw to protect your tooth enamel from the acid.
Green Tea Absorbs Better Without Food
If you’re drinking green tea for its antioxidant content, an empty stomach is actually the ideal time. The primary antioxidant in green tea, known as EGCG, is absorbed three to four times more effectively when consumed without food compared to taking it with a meal. Food substantially blocks absorption whether the tea is consumed alongside breakfast or mixed into something like a sorbet. Drinking green tea on its own, after a period of fasting (like first thing in the morning), gives you the highest blood levels of that compound.
Green tea does contain some caffeine, typically 30 to 50 mg per cup, so if caffeine on an empty stomach bothers you, start with a small cup and see how your body responds. Most people tolerate it well, and the amino acid L-theanine in green tea tends to smooth out caffeine’s sharper effects.
Coffee Is Better After Eating
Coffee stimulates the release of gastrin, a hormone that triggers stomach acid production. It also increases gastric acid secretion through mechanisms beyond just caffeine. On an empty stomach, this surge of acid has nothing to digest, which can cause discomfort, nausea, or heartburn in sensitive individuals.
There’s also a timing consideration. Your body produces cortisol in a natural peak around the time you wake up, part of the cortisol awakening response that helps you feel alert. Drinking caffeine during this peak doesn’t add much alertness and may blunt your natural cortisol rhythm over time. Research on caffeine and cortisol shows that after just five days of regular caffeine intake, the cortisol response to a morning dose was essentially abolished, though afternoon doses still triggered a response. Waiting 60 to 90 minutes after waking, and ideally having something in your stomach first, lets you get more from your coffee without the digestive trade-offs.
Apple Cider Vinegar: Small Doses Only
Diluted apple cider vinegar before meals has gained popularity for blood sugar management, and there’s some evidence to support it. Studies using about 30 ml (two tablespoons) of apple cider vinegar before a carbohydrate-heavy meal found it enhanced glucose uptake and reduced the need for insulin secretion in insulin-resistant individuals. The most commonly studied dose range is 10 to 30 ml per day, diluted in water.
The key word is diluted. Undiluted vinegar is harsh on tooth enamel and the lining of your esophagus. And more is not better. One documented case involved a woman who consumed roughly 250 ml of vinegar daily for six years and ended up hospitalized with dangerously low potassium, muscle cramps, and electrolyte imbalances. Stick to one to two tablespoons in a full glass of water, and drink it through a straw if you make it a daily habit.
Bone Broth for Gut Support
Warm bone broth on an empty stomach delivers a combination of amino acids, including glutamine, glycine, proline, and arginine, along with minerals like calcium, magnesium, potassium, and zinc. These components have been shown to support intestinal barrier function, reduce inflammation in the gut lining, and improve nutrient absorption. A 2025 review of animal and human studies confirmed that bone broth’s benefits for gut health go beyond folk remedy status, with documented effects on intestinal permeability and barrier integrity, particularly relevant for people with inflammatory bowel conditions.
Sipping bone broth first thing coats the stomach gently and provides easily absorbed nutrients without triggering a large insulin response. It’s one of the better options if you find that eating solid food first thing in the morning doesn’t sit well.
Coconut Water for Morning Electrolytes
If you wake up feeling depleted, especially after a night of poor sleep, alcohol, or heavy exercise the day before, coconut water offers a natural electrolyte boost. One cup contains about 470 mg of potassium and 30 mg of sodium, with only 45 to 60 calories and 11 to 12 grams of sugar. Research suggests it’s better than plain water for rehydration, though not necessarily superior to commercial sports drinks.
The one limitation is its low sodium content. Sodium is the primary electrolyte you lose through sweat, so if you’re rehydrating after intense exercise, coconut water alone may not fully replace what you’ve lost. For a typical morning, though, the potassium content makes it a solid choice, especially since most people don’t get enough potassium in their diets.
Skip the Fruit Juice
Fruit juice on an empty stomach causes a rapid, steep spike in blood sugar. Research comparing fast and slow ingestion of 100% apple juice found that drinking it quickly produced significantly higher glucose and insulin spikes at 15 and 30 minutes, along with elevated lactic acid and other metabolic stress markers. Without the fiber that whole fruit provides, and without any fat or protein to slow absorption, the fructose hits your bloodstream fast.
Even sipping juice slowly only partially blunted the spike. Glucose levels still rose, just more gradually, reaching their peak at 60 minutes instead of 30. If you enjoy juice in the morning, it’s far better paired with a meal that includes protein or fat. On a truly empty stomach, juice is one of the less helpful choices you can make.