Vege vs vege

To make up our four starting vegetable divisions, we've sorted vegetables by colour (red/purple, green, yellow/orange, and white). Then we've chosen our top 16 veg based on their levels of vitamin C, the super water-soluble antioxidant with a list of health benefits longer than Irene Van Dyk's legs. (To name just a few: C boosts immunity, protects your skin from sun damage, aids in healing wounds and helps you absorb iron.)

Next, we've pitted the veges against each other within their divisions to find which one ranked highest in the four nutrients women need most.

Round one: folate

You know about this B-group vitamin's role in making healthy babies, and also because of the national debate on whether bakers will have to include folic acid in all bread (a decision that's been delayed). Women need 400mcg per day, or 600mcg just before and during pregnancy, so you need to get it from a variety of foods. The perks of getting your folate RDI don't stop at healthy babies. Folate lowers CRP and homocysteine - two blood compounds that trigger artery inflammation - says dietitian Kathy McManus, director of the department of nutrition at Brigham and Women's Hospital, US. Studies find that high CRP raises heart attack risk and high homocysteine levels are linked with vascular disease and stroke.

Round two: magnesium

This is found primarily in good-for-you foods such as veg, so it says something that more than 54 per cent of 1033 admitted hospital patients in a recent study were low in magnesium, according to the Journal of the American Medical Association. No good, since the Journal of the American College of Nutrition says low magnesium levels elevate blood sugar. (When blood sugar hits a Mt Cook high, your pancreas pumps more insulin, which makes your body store the sugar as fat.) Magnesium also helps maintain normal muscle and nerve function, steadies heart rhythms, and supports your immune system. Women under 31 need 310mg a day, and those over 31 need 320mg.

Round three: iron

Even if you usually get your iron RDI of 18mg, the monthly visit from Auntie Flo can leave you with an iron deficit. Without enough, your brain and muscles can't get enough oxygen, which slashes their efficiency. A recent Penn State University, US, study showed that iron deficiency slowed down female subjects completing mental tasks.

The finals: selenium

This vital trace mineral helps mop up pesky free radicals and boosts protection against heart disease, type 2 diabetes and cancer. It also generates proteins that your immune system needs to stay up and running. And your thyroid can't produce certain hormones without it. (Thyroid hormones control the metabolism of every cell in your body.) Alas, women tend to come up short of the recommended 60mcg a day. The fix: include heaps of vegetables in your diet and, since New Zealand's otherwise lush soils tend to be selenium deficient, consider backing them up with a supplement. The upper limit intake of selenium is around 400mcg a day, so look for a supplement with less than that