Arugula (Rocket)

Health Benefits

Glucosinolates and isothiocyanates. Arugula contains glucosinolates, the sulfur compounds characteristic of the cabbage family, and when the leaf is cut or chewed an enzyme reaction forms isothiocyanates such as erucin. That is a statement about composition; studies in people on arugula alone are scarce.

What the cruciferous epidemiology can and cannot say. Several epidemiological studies have observed populations that eat large amounts of cruciferous vegetables. Correlations seen in observational work do not establish cause, so for arugula the defensible statement stops at its membership in that family.

Nitrate. Along with spinach and beet, arugula is classed among the leafy greens high in dietary nitrate. The pathway by which nitrate becomes nitric oxide in the body has been studied for decades, but that does not mean eating this green wards off any particular illness.

Extract studies are not the food. Test-tube studies on arugula leaf extract have been reported, and an extract is not the same thing as eating the leaf itself. Separately from those studies, the leaf is confirmed to contain antioxidant constituents such as vitamin C, carotenoids and flavonoids.

Nutrition

• Glucosinolates (source of the peppery bite) — the sulfur compounds behind the brassica bite
• Vitamin K and folate (abundant) — micronutrients common in dark leafy greens

Glucosinolates Arugula contains glucosinolates, the sulfur compounds common to Brassicaceae crops. Glucoerucin is among the forms reported in the leaf, and the profile is not the same as that of broccoli, whose marker compound is glucoraphanin. These compounds create the peppery, pungent flavor of the leaves, and their breakdown products are the precursors examined in laboratory research.

Isothiocyanates When glucosinolates are broken down by the enzyme myrosinase, isothiocyanates are formed, and in arugula the representative one is erucin, which comes from glucoerucin. Sulforaphane arises from the glucoraphanin of the broccoli group, so it is hard to list it as a principal breakdown product of arugula. These compounds have long been handled in test-tube and animal laboratory work, and what changes in the body when a person eats arugula has not been established.

Beta-carotene, lutein and zeaxanthin The deep green leaves concentrate carotenoids such as beta-carotene, lutein and zeaxanthin. Beta-carotene converts to vitamin A in the body, and it is established that lutein and zeaxanthin accumulate in the retinal macula. That does not mean eating this green wards off any particular eye disease.

Vitamin K Per 100 g of raw leaf, arugula sits among the leafy vegetables that carry a fair amount of vitamin K. Spinach and kale hold considerably more, however, so it cannot be described as ranking at the top of the leafy greens. Vitamin K takes part in blood coagulation and bone metabolism, and is the nutrient required to activate osteocalcin, the protein that binds calcium into bone.

Vitamins C and A, folate, calcium, iron and magnesium It holds a balanced range of micronutrients including vitamins C and A along with folate, calcium, iron and magnesium. The leaves are tender yet mineral-dense, so volume for volume the nutrient density is higher than that of lettuce.

Nitrate Like spinach and beet, it ranks among the leafy vegetables highest in nitrate concentration. Ingested nitrate passes through oral microbes and the stomach, moving via nitrite to nitric oxide (NO), and that pathway itself has been studied for decades. These are reports about food intake, and they do not mean the treatment or prevention of any disease.

Flavonoids (quercetin and kaempferol) and phenolic acids It contains flavonoids such as quercetin and kaempferol along with a range of phenolic acids. These are constituents handled in laboratory research, and they also give arugula its characteristic bitter aftertaste.

Pairings

○ Olive oil, balsamic vinegar, and Parmesan — This is the classic Italian arugula salad. The fat in olive oil boosts carotenoid absorption, the acidity of balsamic softens the rough edge of the peppery leaves, and the savory depth of Parmesan rounds out the flavor.

○ Prosciutto and feta — Peppery, pungent leaves find their balance against salty cured meats and cheese. The saltiness, protein, and fat of prosciutto and feta tame arugula's bite while raising the overall nutritional density of the meal.

○ Tomato and mozzarella — A twist on Caprese that swaps arugula for the basil, or adds it alongside. The lycopene in tomato and the protein in mozzarella pair with arugula's carotenoids and isothiocyanates to create a textbook Mediterranean plate. Tomato

○ Pine nuts and other nuts — Stir pine nuts, walnuts, or almonds into an arugula pesto or scatter them over a salad. The unsaturated fats in nuts aid the absorption of fat-soluble nutrients, and their nutty richness balances the peppery leaves. Korean Pine Nut

○ Lemon and orange — A squeeze of lemon or orange juice boosts vitamin C and brightens the impression of the peppery leaves. It also helps slow oxidation, keeping the salad from discoloring as quickly.

○ Watermelon — It sounds unlikely, but a summer salad of peppery arugula, sweet watermelon, and salty feta is a Western favorite. The sweet-salty-spicy trio plays off one another on the palate, sparking an appetite that summer heat can easily dull. Watermelon

△ Anticoagulants — Arugula is high in vitamin K, so for people on anticoagulants like warfarin, suddenly eating much more or much less can destabilize the medication's effect. Rather than avoiding it entirely, the safe approach is to keep your intake steady and consistent.

△ Hypothyroidism — The glucosinolates in cruciferous vegetables are known to partially interfere with thyroid hormone synthesis when eaten raw and in large amounts. People with hypothyroidism should eat arugula cooked rather than raw and avoid consuming large quantities in a single meal.

△ Long storage: wilting kills the aroma and peppery bite — The thin leaves wilt quickly in storage, losing their signature aroma and peppery kick. Even refrigerated, the flavor fades within days, so it's best enjoyed fresh, soon after purchase.

Varieties

• Salad rocket (standard line) (Seed) — The most common line. Broad leaves, mild scent, and first picking about a month after sowing.
• Wild rocket (Seed) — Finely cut leaves and a much sharper bite. Slow to grow but picked over several seasons.
• Broad-leaf line (Seed) — Large leaves give a big pick at once, but it bolts fast in heat, so cut the leaves young.