Raw foods and other "nature" stuff

SF

A friend of mine rejects boiled vegetables, as he sais all the nutrients are destroyed.
I hold that only some of the nutrients are destroyed and there isn't much difference between eating boiled and unboiled stuff.

What's lost in the process can be obtained from other aliments.
Who's right?

Schrodinger's Dog

Some are lost not all, especially if you stir fry or par boil. In particular vitamin C loses out quite substantially, but the other vitamins are a little more resilient, so much of them remain, if they didn't then cooking food would leave us with sever vitamin deficiencies.

So yeah your friend is wrong.

You might like to know that the majority of vitamin C in the West is more commonly obtained from eating potatoes, it's the sheer amount. And when was the last time you ate a raw spud?

LtStorm

Some of the nutrients are lost, yeah, but a much larger portion of the bacteria that are present in the vegetable are destroyed too. Which is one of the trade-offs on cooking food; lose some of the healthy stuff, but kill a lot more of the unhealthy stuff.

jim mcnamara

There is some fog here. You can kill bacteria by washing. If there are pathogenic bacteria inside vegetable tissues something is seriously wrong with the food supply. Yes high tempartures do kill bacteria, but they should have been removed or been pretty much absent to start with.

Next, digestibility of vegetables increases enormously when they are cooked. Almost all vitamins can be lost - to a lesser or greater degree during cooking. However the availability of nutrients increases. That's what digestibility means.

DaveC426913

Don't forget that, independent of chemical destruction of nutrients, there is also physical removal of those nutrients. The boiling process ruptures the cells, and much of that yummy goodness is lost into the water. The water may or may not be consumed.

glondor

I understand the antioxident properties Of tomatoes are greatly increased by eating them cooked. Pasta sauce is better than sliced tomatoes.

Moonbear

There are some conflicting ideas presented here (or at least a few differences of opinion...destruction of nutrients, leeching of nutrients into the water, enhanced digestibility of the remaining nutrients, improvement of other nutrient properties...). I'd like to ask folks to provide some sources to back up claims. I think that will help SF to best explain this to his friend too by backing it up with some solid sources. I just want to be sure we're not all spreading some common misconceptions (I don't know...I just have heard such debates without sources before, so am not sure how much of what we "know" on this topic is based in science and how much is what we "heard somewhere.") I'm sure nutrition and food scientists have studied such questions, and sources must be available to provide good answers.

Evo

I can post proof of the nutritional differences in cooking breaking down cells that allow nutrients to be absorbed as in the case of collard greens, an excellent example, but I can't access the website from home, they have an error in their scipting that conflicts with my browser version.

Something not brought up is the combination of foods, for example, most people think spinach is an excellent source of iron, not so. The naturally occuring oxalic acid prevents absorbtion of the iron, as does eating milk products. That spinach dip you think is healthy? Think again.

http://health.rutgers.edu/factsheets/iron.htm

Although not a scientific study, this article will give some background, which can be further researched, into why cooking food is often beneficial and how certain foods eaten together can be beneficial or non-beneficial.

http://query.nytimes.com/gst/fullpag...pagewanted=all

Evo

I'm not going to have time to look up the other site, so here is this link about a recent study.

Cooking Can Preserve, Boost Nutrient Content Of Vegetables

http://www.sciencedaily.com/releases...1224125524.htm

glondor

Here is a science blurb about the advantages of cooked tomatoes over raw.

http://www.sciencedaily.com/releases...0619073727.htm

Ouabache

According to this study, many cooked vegetables offer higher availability of nutrients.
They noted that the carotenoids in cooked & mashed carrots are absorbed 5X more, compared to eating them raw. Beta-carotene is high, not only in carrots but also spinach, broccoli and collards. Another carotenoid, lycopene (found in tomato and watermelon) is also very stable after cooking.

Schrodinger's Dog

Please tell me that I was right about vitamin C at least.

DaveC426913

But who wants to eat cooked watermelon??

Ouabache

I've seen folks from China, stir-frying the rind. I would venture there is lycopene in the rind.
"In China, they are stir-fried, stewed, or more often pickled. When stir-fried, the de-skinned and de-fruited rind is cooked with olive oil, garlic, chili peppers, scallions, sugar and rum" ref1


Schrodinger's Dog, yes Vitamin C is heat labile. Some will be lost during cooking. (ref2)