Top sirloin steak can certainly be lean and low in calories, but if you're one who prefers a lot of marbling — or ribbons of fat — in your steak, you'll get way more fat and calories than you may realize. However, sirloin steak nutrition also includes protein and several vitamins and minerals.
Top Sirloin Calories and Protein
Generally the more marbling you see in your steak, the less protein you'll get, since fat takes up a bigger chunk of the weight. For example, that 3-ounce top sirloin with one-eighth an inch of fat has about 23 grams of protein. The National Academies of Sciences recommends a range of 50 to 175 grams of protein for a 2,000-calorie diet — 10 to 35 percent of calories — so a 3-ounce sirloin steak can offer almost half of your daily protein needs.
Be Aware of Fat
You'll get up to 13 grams of total fat from a 3-ounce broiled top sirloin steak, depending on the amount of marbling and edge fat. While some fat in your diet is essential to absorb certain vitamins and produce hormones and enzymes, not all fats are good for you. Over one-third of the total fat in any top sirloin steak is saturated, a type of fat linked to heart disease.
Less than 10 percent of calories should come from saturated fat, according to the 2015-2020 Dietary Guidelines for Americans. For a 2,000-calorie diet, this is a maximum of 22 grams of saturated fat. A fully trimmed 3-ounce top sirloin has less than 4 grams of saturated fat. But top sirloin with visible fat can have more than twice the amount of saturated fat, almost 50 percent of your daily saturated fat allowance.
Minerals in Top Sirloin
Lean, fully-trimmed steaks have a slightly higher concentration minerals, but they all have a similar amount. One 3-ounce top sirloin nutrition facts includes 4.4 milligrams of zinc, a mineral that boosts your immune system, heals wounds and helps produce enzymes. That meets 40 percent of the daily zinc requirement for men and 60 percent for women, according to Harvard Health.
Red meat, in general, is rich in iron to improve oxygen transportation throughout your body. A 3-ounce prepared top sirloin has 9 percent of your iron recommendation for woman and 16 percent of the requirement for a man. That same steak has close to 25 percent of your daily phosphorus needs to build up bone tissue.
Get Your B Vitamins
Top sirloin is one of the richest sources of B vitamins. You'll get around 50 percent of the vitamin B12 you need— as reported by Harvard Health — from a 3-ounce top sirloin. B12 keeps your red blood cells healthy, protects brain cells and plays a role in sending messages around.
You'll even get small amounts of five other B vitamins — thiamin, riboflavin, niacin, folate and B6 — to boost your metabolism and help your body breakdown food.
- Harvard Health Publishing: "Listing of Vitamins"
- National Academies of Sciences: "Macronutrients"
- Health.gov: "2015-2020 Dietary Guidelines for Americans"
- USDA FoodData Central: "Beef, Top Sirloin, Steak, Separable Lean and Fat, Trimmed to 0" Fat, Choice, Cooked, Broiled"
- USDA FoodData Central: "Beef, Top Sirloin, Steak, Separable Lean and Fat, Trimmed to 1/8" Fat, Choice, Cooked, Broiled"