How to cook vegetables to get the most nutrients

Posted by kathryn in Vegetables and Q & A Thursday

First up in October’s Q & A Thursday is a question from Andrea:

I’ve often heard that you should steam vegetables, rather than boil them, to gain more nutrients out of them. However, I am not sure why this is so. Is this because (a) nutrients are water soluble, so when you boil them and drain off the water, you are pouring the nutrients away? Or (b) boiling vegetables actually destroys the nutrients somehow?

Vegetables contain a number of different nutrients. Vitamins, minerals, fibre, antioxidants, as well as carbohydrates and even tiny amounts of protein. While we can get carbohyrates, protein and fibre from other foods, we rely on vegetables to provide many of the vitamins, minerals and antioxidants we need for good health.

Most healthy eating guidelines include recommendations on how vegetables should be cooked. To keep your vegies as jam-packed with nutrients as possible, some cooking methods are better than others.

Some nutrients are water soluble

Vitamins are split into two main groups. Some of them like Vitamin C and the B group, are water soluble. While others, like A, E and D are fat soluble. If you boil vegetables, then some of these water soluble nutrients leach out into the cooking water and when you drain the vegies these nutrients are lost down the sink.

If you’re cooking vegetables in a soup or stew, some of these nutrients will be retained – as you’re not draining away the juices.

Some nutrients are fragile

Some of the water soluble nutrients, like vitamin C, are also quite fragile. When exposed to heat they start to degrade.

Which means extensive cooking at high temperatures is also a problem for these water soluble nutrients.

Of course it’s not that simple

If you’ve just read the above, it sounds like we should all be eating raw vegetables. However, while some nutrients are lost during cooking, others actually become more available and useful. This is true of the lycopene in tomatoes, the iron in spinach and a number of others.

The top 5 guidelines on how to eat vegetables

  1. The number one priority is to eat vegetables, no matter how they are prepared. Without daily serves of vegetables your diet is deficient.
  2. Eat a variety of vegetables. They all contain different vitamins and antioxidants. By eating a variety you are ensuring your diet is the best it can be.
  3. Prepare you vegetables in a variety of different ways. To get the most out of your vegies eat them both raw and cooked.
  4. Try not to over-cook vegetables. Lightly steam, stir fry or micro-wave the majority of vegetables you eat. This reduces the nutrient loss.
  5. Cook and eat vegetables with a small amount of oil, as this helps you absorb the fat-soluble vitamins and antioxidants.

What’s your favourite way of eating vegetables?

What is Q & A Thursday?

This post is part of Q & A Thursdaya monthly burst of blogging, where you get to dictate the subject matter. Q & A Thursday is all about simple, practical answers to food and diet dilemmas sent in by readers.


Comments

Johanna 09 October, 2008

I love microwaving vegetables because it is quick and I find this an easier way to avoid overcooking – esp green veg like broccoli and asparagus. I also love roasting veg like pumpkin and cauli.

I was surprised to see you recommending to eat vegies with a little oil – never heard this before – well not for vitamins


Melody 10 October, 2008

I love roasting mine in the oven with a little bit of cooking spray or olive oil and a sprinkle of some sort of spice mix. I especially prefer my broccoli, cauliflower and green beans to be cooked this way. They caramelize and get oh so yummy! I also grill zucchini, mushrooms, yellow squash and onions quite frequently on my indoor grill with a bit of cooking spray and some kind of seasoning mix (whatever I’m in the mood for). I often top them with a bit of salsa or a drizzle of balsamic and have them, along with a serving of lean protein, for my dinner.

I eat a fair amount of raw veggies too, usually in salads or with hummus. I love veggies!


kathryn 10 October, 2008

Johanna – you only need to use a tiny amount of oil and I’m pretty sure other fat containing substances would also work – for example avocado. But yes, it does help absorb the fat soluble vitamins and antioxidants.


Maja 12 October, 2008

I’d usually steam green beans, red beets, broccoli, cauliflower and potato, stir-fry carrots, green peas, onions and sauté tomato, peppers and garlic for the tomato sauce.
I like my vegetables crunchy, so I don’t expose them to heat for too long.
However, lately I’m going crazy for grated raw red beets with carrot, drizzled with some simple vinaigrette. I try to eat a portion of raw vegetables every day. I like them too much!


Leave a comment

(All comments are moderated and may take a while to be displayed)