Broccoli packs a surprisingly dense range of vitamins, minerals, and plant compounds into every serving. A single cup of chopped broccoli delivers near-complete daily doses of certain vitamins while also providing minerals and unique antioxidants that are harder to find in other vegetables.
Vitamins: Where Broccoli Really Shines
Vitamin K is broccoli’s standout nutrient. Just half a cup of cooked, chopped broccoli contains 110 micrograms of vitamin K1, covering 92% of the Daily Value. Your body uses vitamin K1 to form blood clots and maintain bone density, so a regular serving of broccoli essentially handles that need on its own.
Vitamin C is the next major contributor. One cup of cooked broccoli provides about 51 milligrams, which covers more than half of what most adults need daily. Vitamin C supports immune function and helps your body build collagen for skin and connective tissue. It also plays a practical role in how you absorb other nutrients in broccoli, which we’ll get to below.
Broccoli is also a solid source of folate (vitamin B9), with a cup of cooked broccoli delivering around 103 micrograms. That’s roughly a quarter of the daily recommendation. Folate is essential for cell division and DNA repair, making it especially important during pregnancy. You’ll also get smaller but meaningful amounts of vitamins A, B6, and E in each serving.
Minerals in Every Serving
A cup of raw, chopped broccoli contains about 288 milligrams of potassium, 43 milligrams of calcium, and small amounts of manganese, iron, and phosphorus. Potassium helps regulate blood pressure and fluid balance, and while broccoli isn’t as potassium-rich as a banana, it contributes meaningfully when eaten regularly as part of a varied diet.
The calcium in broccoli is worth noting for people who limit dairy. At 43 milligrams per cup raw, it’s not a powerhouse, but broccoli’s calcium is more easily absorbed than calcium from many other plant sources like spinach, which contains compounds that block absorption. The iron in broccoli is non-heme iron, the type found in all plant foods, which your body absorbs less efficiently than the iron in meat. Here’s where broccoli has a built-in advantage: its vitamin C content enhances non-heme iron absorption when consumed at the same time. So broccoli essentially helps you absorb its own iron.
Sulforaphane: Broccoli’s Signature Compound
Beyond standard vitamins and minerals, broccoli contains a group of sulfur-based compounds called glucosinolates, the most studied being glucoraphanin. When you chew or chop broccoli, an enzyme in the plant converts glucoraphanin into sulforaphane, a compound with antioxidant and anti-inflammatory properties. Sulforaphane has been linked to cellular protection and is a major reason broccoli gets singled out among vegetables in nutrition research.
Raw broccoli and lightly cooked broccoli contain the most sulforaphane, because the enzyme responsible for the conversion is sensitive to heat. Broccoli sprouts contain especially concentrated amounts of glucoraphanin, sometimes 10 to 100 times more than mature broccoli heads.
Fiber and Macronutrients
One cup of chopped, cooked broccoli has about 5 grams of fiber, a mix of soluble and insoluble types. Soluble fiber feeds beneficial gut bacteria, while insoluble fiber helps move food through your digestive system. For a non-starchy vegetable, that’s a substantial amount. The same serving has roughly 4 grams of protein, 11 grams of carbohydrates, and only about 55 calories, making it one of the most nutrient-dense foods per calorie you can eat.
How Cooking Affects the Nutrients
The way you prepare broccoli changes what you actually absorb. Boiling is the most destructive method for water-soluble nutrients like vitamin C and the glucosinolates that produce sulforaphane. These compounds leach into the cooking water, so unless you’re drinking the broth, a significant portion is lost.
Steaming is the best cooking method for preserving broccoli’s full nutrient profile. Steamed broccoli retains more glucosinolates compared to boiled or fried broccoli, and it keeps a higher percentage of its vitamin C intact. Roasting and stir-frying fall somewhere in between, with shorter cook times preserving more nutrients. If you prefer softer broccoli, steaming until just tender (about 4 to 5 minutes) gives you the best balance of texture and nutrition.
Fresh vs. Frozen Broccoli
Frozen broccoli is generally higher in vitamins C and A as well as some antioxidants compared to fresh broccoli that has been sitting in your refrigerator for several days. Fresh vegetables lose nutrients during transit, on the store shelf, and in your crisper drawer, while frozen broccoli is processed and flash-frozen shortly after harvest, locking in nutrients at their peak.
There’s one trade-off, though. Frozen broccoli is blanched before freezing to preserve color and texture, and that blanching process reduces some of the compounds needed to produce sulforaphane. If sulforaphane is a priority for you, fresh broccoli (eaten within a few days of purchase) or raw broccoli sprouts are the better choice. For overall vitamin and mineral content, frozen broccoli is a perfectly good option and often the more practical one.