Food labels exist to give you the information you need to compare products, manage your diet, and avoid ingredients that could harm you. They’re required by federal law on nearly all packaged foods, and the FDA sets strict rules about what must appear, where it must appear, and how large the text needs to be. At their core, food labels serve three purposes: disclosing nutritional content, identifying allergens and ingredients, and preventing manufacturers from making misleading claims.
What the Nutrition Facts Panel Tells You
The Nutrition Facts panel is the most recognizable part of any food label. Every panel must list calories, total fat, saturated fat, trans fat, cholesterol, sodium, total carbohydrates, protein, and four specific micronutrients: vitamin D, calcium, iron, and potassium. All of these values are tied to a single serving size, which is based on the amount people typically eat in one sitting, not necessarily the amount in the package.
Serving sizes aren’t set by manufacturers. The FDA maintains a list of reference amounts for each food category, and manufacturers convert those reference amounts into a familiar household measure like “1 cup” or “about 12 chips.” This standardization is what makes it possible to compare two different brands of yogurt or cereal side by side.
Each nutrient also shows a Percent Daily Value (%DV), which tells you how much of your daily recommended intake one serving provides based on a 2,000-calorie diet. The FDA uses a simple rule of thumb here: 5% DV or less is considered low, and 20% DV or more is considered high. That quick mental shortcut helps you identify products that are high in nutrients you want (like fiber or calcium) and low in ones you’re trying to limit (like sodium or saturated fat).
Why Added Sugars Get Their Own Line
One of the more recent additions to the Nutrition Facts panel is a separate line for added sugars, listed directly below total sugars. The distinction matters because added sugars contribute calories without the vitamins, minerals, or fiber that naturally occurring sugars in fruit or milk come packaged with. Federal dietary guidelines recommend keeping added sugars below 10% of your total daily calories, which works out to about 50 grams on a 2,000-calorie diet.
The ingredient list is where added sugars can get tricky. Sugar appears under dozens of names: cane sugar, turbinado sugar, high-fructose corn syrup, rice syrup, agave, honey, molasses, and caramel are all common. Any ingredient ending in “-ose” (glucose, fructose, maltose, dextrose, sucrose) is also a sugar. Terms like “glazed,” “candied,” or “caramelized” signal that sugar was added during processing. Scanning the ingredient list alongside the Nutrition Facts panel gives you the full picture.
Allergen Disclosure
For people with food allergies, labels can be life-saving. Federal law requires manufacturers to clearly identify nine major allergens: milk, eggs, fish, shellfish, tree nuts, peanuts, wheat, soybeans, and sesame. These nine account for the vast majority of serious allergic reactions. The allergen must be named in plain language, either within the ingredient list itself or in a separate “Contains” statement immediately after it, so you don’t need to decode chemical or technical names to spot a risk.
How Ingredient Lists Work
Ingredients are listed in descending order by weight. The first ingredient makes up the largest proportion of the product, and the last ingredient makes up the least. This ordering is one of the most useful tools on the entire label. If sugar or a sugar synonym appears in the first three ingredients of a cereal or snack bar, that product is heavily sweetened regardless of what the front of the package says. If whole wheat flour is listed first but enriched white flour appears second, the product is a blend rather than a true whole-grain food.
What “Healthy” and Other Claims Actually Mean
Front-of-package claims like “low fat,” “good source of fiber,” or “healthy” aren’t just marketing language. Each one has a specific regulatory definition, and products that don’t meet the criteria can’t legally use the term. Health claims that link a food to reduced disease risk, such as “diets low in sodium may reduce the risk of high blood pressure,” must meet an even higher bar. The FDA requires significant scientific agreement among qualified experts before authorizing any such claim.
The FDA finalized an updated definition of “healthy” in December 2024. To carry the claim now, a product must contain a meaningful amount of at least one recommended food group (fruits, vegetables, whole grains, dairy, or protein) while staying under specific limits for added sugars, sodium, and saturated fat. For a grain product, that means at least three-quarters of an ounce of whole-grain equivalent, no more than 5 grams of added sugar, no more than 230 milligrams of sodium, and no more than 1 gram of saturated fat per serving. The thresholds vary by food category, but the underlying principle is the same: a product labeled “healthy” must actually contribute nutrients, not just avoid excess of one.
Date Labels Are About Quality, Not Safety
Date stamps are one of the most misunderstood parts of food packaging. With a single exception, none of them are safety dates, and none are required by federal law. “Best if Used By” indicates when the product will taste or perform at its peak. “Sell-By” is inventory guidance for the store. “Use-By” is the manufacturer’s recommendation for peak quality. “Freeze-By” tells you when to freeze if you want to preserve that quality. In all of these cases, the food may still be perfectly safe to eat after the printed date.
The one exception is infant formula. Federal regulations require a “Use-By” date on infant formula, and that date is a true safety and nutrition deadline. It ensures the formula still contains the nutrient levels listed on the label. For every other product, the date is a quality suggestion, not a health warning.
Preventing Misleading Packaging
A less visible but equally important purpose of food labeling law is preventing misbranding. The FDA can take action against any product whose label contains false or misleading claims about the food, about competing products, or about drugs and supplements. Regulations also specify that required information must appear prominently: text can’t be too small, can’t blend into the background, and can’t be buried behind decorative graphics or crowded by other printed material. The goal is that every required statement is easy to find and read under normal shopping conditions, not hidden where you’d need a magnifying glass or a reason to go looking.
Taken together, these requirements turn a food label into a standardized, comparable snapshot of what’s actually inside the package. The system isn’t perfect, but knowing how to read the panel, the ingredient list, and the claims gives you a reliable way to evaluate almost any packaged food before you buy it.