You measure sugar and salt by weight (grams) for accuracy or by volume (teaspoons, tablespoons, cups) for convenience. One level teaspoon of granulated sugar weighs about 4 grams, while one level teaspoon of table salt weighs about 6 grams. That difference matters more than you’d expect, whether you’re following a recipe, reading a nutrition label, or tracking your daily intake for health reasons.
Weight vs. Volume in the Kitchen
A kitchen scale gives you the most reliable measurement for both sugar and salt. Volume measurements (teaspoons, cups) shift depending on how tightly you pack the ingredient, grain size, and even humidity. A “heaping” teaspoon of sugar can hold nearly twice as much as a level one. Brown sugar packs denser than granulated. Coarse sea salt takes up more space per gram than fine table salt. If a recipe matters to you, weigh it.
When you don’t have a scale, the standard conversions work well enough for everyday cooking. One level US teaspoon holds roughly 4.2 grams of granulated white sugar and about 6 grams of fine table salt. One tablespoon is three teaspoons, so that’s about 12.5 grams of sugar or 18 grams of salt. For cup measurements, a cup of granulated sugar is approximately 200 grams, while a cup of table salt is closer to 290 grams.
Reading Sugar and Salt on Nutrition Labels
Nutrition labels list sugar in grams and salt as “sodium” in milligrams. These are two different things. Salt is sodium chloride, and sodium makes up only about 40% of salt’s weight. To convert between them: multiply sodium in grams by 2.5 to get the equivalent amount of table salt. So 800 mg of sodium on a label equals about 2 grams of salt.
For sugar, the quick mental math is straightforward: divide the grams on the label by 4 to get teaspoons. A can of soda listing 39 grams of sugar contains roughly 10 teaspoons. That makes label numbers much easier to visualize.
Daily Intake Recommendations
The World Health Organization recommends adults consume less than 5 grams of salt per day, which equals less than 2,000 milligrams of sodium. That’s just under one teaspoon of table salt total, including everything already in your food. Most people consume more than double that amount.
For added sugars, the WHO suggests keeping intake below 10% of total daily calories, with additional benefits below 5%. On a 2,000-calorie diet, 5% works out to about 25 grams, or roughly 6 teaspoons of added sugar per day.
How Sugar Is Measured in Your Blood
When your doctor checks your blood sugar, they’re measuring the concentration of glucose in your blood. In the United States, results come in milligrams per deciliter (mg/dL). Most other countries use millimoles per liter (mmol/L). A fasting blood sugar of 100 mg/dL equals 5.6 mmol/L. To convert, multiply mmol/L by 18 to get mg/dL, or multiply mg/dL by 0.0555 to get mmol/L.
A standard finger-prick glucose meter measures sugar directly from a drop of capillary blood. Continuous glucose monitors work differently. They use a tiny sensor inserted just under the skin that measures glucose in the fluid between your cells, not in your blood directly. Glucose diffuses from your bloodstream into this fluid, so the readings track your blood sugar but with a lag of roughly 4 to 26 minutes. That delay is why a continuous monitor can disagree with a finger prick during rapid changes, like right after a meal or intense exercise.
How Salt Is Measured in Your Blood
A basic metabolic panel, one of the most common blood tests, includes a sodium level. Your body maintains blood sodium in a tight range of 137 to 142 milliequivalents per liter. Values outside this window signal problems with hydration, kidney function, or hormone balance rather than simply eating too much or too little salt.
Doctors sometimes order a 24-hour urine collection to estimate actual sodium intake. You collect all urine over a full day, and the lab measures how much sodium your kidneys excreted. Since the body absorbs nearly all dietary sodium from the digestive tract, urinary output closely reflects what you ate. The test accounts for natural variation, since sodium excretion during the night drops to about 20% of peak daytime rates.
Measuring Sugar Concentration in Liquids
Outside the kitchen and the clinic, sugar concentration in liquids is measured on the Brix scale, used widely in winemaking, brewing, juice production, and agriculture. One degree Brix (°Bx) equals 1 gram of sucrose per 100 grams of solution, essentially a percentage by weight.
The tool for this is a refractometer. You place a few drops of liquid on a glass prism, look through the eyepiece toward a light source, and read where the light and dark fields meet on a graduated scale. The device works because dissolved sugar bends light in a predictable way: the more sugar present, the more the light refracts. Digital refractometers do the same thing electronically and automatically correct for temperature, which affects readings. A ripe grape might measure 22 to 26 °Bx, while orange juice typically falls around 11 to 14 °Bx.