[iain]

I had a friend years ago who was into his food combining. If I understood correctly carbs and protein are digested best in alkaline and acidic environments (think it was that way round) and that if you eat both at the same time your stomach has to do far more work and it's more likely stuff isn't going to be digested properly and be stored as fat. So the idea is you only eat one food type at a time, it gets digested more efficiently, and then you have the next food type, giving you more energy and making you lose weight at the same time 

I think the acid/alkali thing is FACT

[jfw]

the glycaemic index tells you how quickly energy from food can be released (ok simplistic definition)

in general the quicker that energy is delivered, the more of a peak trough hunger cycle you are likely to get in to - ie wham a hit of "sugar", then ooh must replace it

by combining proteins and carbs in one meal - you not only feel satisfied, so the theory goes, but you feel satisfied for longer.

i don't see how poorly digested food is more likely to get turned into fat??

[rich d]

The acid alkali thing makes no sense to me. Are you suggesting that your stomach senses what type of food you've eaten and changes its PH accordingly?

[slackline]

Digestion doesn't just occur in the stomach, thats where everything gets churned up with stomach acid & enzymes to start breaking it down.  Absorption of food then takes place in the large and small intestine as the food pass further along the alimentary canal towards the poop shoot which usually takes over a day.

So anyone positing that you can only absorb one food type at a time needs to reconcile this with everything that they've eaten in the previous +24 hours.

[Obi-Wan is lost...]

Just catching up on this thread. The number 5 in 5 a day is rather arbitrary. The government worked out that the average intake was around 3 portions and decided we needed to consume more. 5 was chosen as a realistic achievable goal. To be more accurate it should be 'at least 5 a day' although they wanted to keep the message as simple as possible.

Mrs Obi was down at Western Park museum yesterday where they have just opened a new exhibition on food. Sponsered by the governments Change4LIfe anti child obesity campaign, they had lots of info and stands promoting diet soft drinks over fruit juice which contains 'lots of sugar' and is therefore bad. Apprantently totally unaware of the growing research that has been circulating for several years linking sweeteners to weight gain not to mention the links with cancer the people manning the stands were insistant that pure fruit juice was unhealthy due to it's high sugar content. Apparently contradicting the '5 a day' advice.

[Clart]

I had a friend years ago who was into his food combining. If I understood correctly carbs and protein are digested best in alkaline and acidic environments (think it was that way round) and that if you eat both at the same time your stomach has to do far more work and it's more likely stuff isn't going to be digested properly and be stored as fat. So the idea is you only eat one food type at a time, it gets digested more efficiently, and then you have the next food type, giving you more energy and making you lose weight at the same time 

I think the acid/alkali thing is FACT

It sounds like you are referring to the Hay Diet (Hay, William 1933). If you were digesting food in a lab then it would make some sense I suppose but fortunately your body is a clever bit of kit that sorts it all out for you, as Slackline implied above. The other problem is that many foods contain both protein and carbohydrate, e.g. lentils, so you'll have a hard time separating them out anyway.

In conclusion, don't bother, a balanced diet is better.

[iain]

The acid alkali thing makes no sense to me. Are you suggesting that your stomach senses what type of food you've eaten and changes its PH accordingly?

I wasn't suggesting that, merely re-iterating what my friend had told me and perhaps showing my utter ignorance of the subject at the same time  ???

[Jaspersharpe]

they had lots of info and stands promoting diet soft drinks over fruit juice which contains 'lots of sugar' and is therefore bad. Apprantently totally unaware of the growing research that has been circulating for several years linking sweeteners to weight gain not to mention the links with cancer the people manning the stands were insistant that pure fruit juice was unhealthy due to it's high sugar content. Apparently contradicting the '5 a day' advice.

Jesus. 

Change4Life sponsored by McDonalds and Coke?

[Lund]

I'm a bit surprised this thread didn't get updated with this bobbins.  I didn't do it, as I've been crushing in font, eating about none a day.

http://www.newscientist.com/blogs/shortsharpscience/2010/04/five-fruit-and-veg-a-day-wont.html

But returning to the overall question of whether it is still worth eating 5-a-day, the major reason not to stop yet is spelled out by Willett: where fruits and vegetables may be failing against cancer, they are certainly succeeding against other diseases, especially coronary heart disease, obesity and constipation. In exactly the same EPIC population where fruit failed against cancer, those consuming at least 5-a-day lowered their risk of coronary heart disease or stroke by 30 per cent compared with those on less than 1.5 servings a day.

Perhaps unsurprisingly for the new scientist, they don't do a great job of joining the dots and explaining the difficulty with separating diet from lifestyle, but fundamentally it seems from this and other write-ups that there is nothing in fruit and veg that means eating five different kinds a day will increase your health - certainly with respect to cancer.

On the other hand, nobody is arguing that being a fat bastard is a good way to go to an early grave, so eat those greens as eating them means you're not eating flab pie and thus getting fat and dieing young (rather than in a nursing home, senile and sat in your own urine, aged 900).