That's annoyingly normal - he went vegan, feels great and thinks everyone should try it for a week, now drinking milk and eating meat makes him feel ill.

He doesn't explore though; could he be feeling better simply from eating less? Or more? Or more greens, or more of a particular nutrient? Or less of one specific thing he doesn't digest well? Or does the change in diet make him sleep differently and that's why he feels better? Is it just the act of change itself that does it?

And does he now feel bad about eating animal products and that makes him respond badly? In the comments he refuses to test it and isn't interested in finding out. Does raw animal produce do the same? Unpasteurised milk, raw meat or fish? What about goat or sheep milk? Or byproducts?

I am of course interested in the mysterious weight which lifted from him such as the "annoyance of getting out of a chair", but all sorts of strange practices practitioners claim unverifiable things like that.

Does anybody like this measure anything quantitatively?

I suspect most of his effects were psychological. He expected going vegan to have wonderful effects, so it did.

A lot of the feeling bad/sick is psychological. (Well for me at least). Being a veggie (15 years+), if i eat meat inadvertently (happens rarely) I get an automatic gag reflex.

>"annoyance of getting out of a chair" yeah.. i don't know about that..

There’s something to be said about noticing that things are different after making a change, like going vegan.

I’ve been vegan for nearly 12 years, but I’ll never forget experiencing all of the same feelings the author described.

And when friends go vegan for some period of time, even a little as a week, they report the same sorts of things.

Until the iPhone app with the required hardware attachment is available that provides realtime nutritional and well-being analytics, people reporting that they feel better when they don’t eat meat and dairy products is going to have to suffice for now.

Might want to read this for counter-balance: http://voraciouseats.com/2010/11/19/a-vegan-no-more/

I did try going vegan for a while - nearly two months. It made me feel cold, sick, miserable and lethargic. I have met some vegans and a lot of them do not look very healthy.

If you want to eat healthier, meat is not the problem. It's sugar.

Both are a problem. There is increasing evidence that eating meat causes many long term problems. (http://en.wikipedia.org/wiki/Red_meat#Health_risks) Additionally, see the news in the US in the past few days that supposedly ~50% of meat being currently sold in the US is contaminated (http://latimesblogs.latimes.com/dailydish/2011/04/gross-.htm...). And don't forget that raising animals for meat consumption is just terrible for the environment. I still eat meat, but I'm cutting way back and I feel really bad about it when I still do.

Perhaps you were just not getting enough protein in your vegan attempt? Or eating the right iron rich foods? One of my friends is a vegetarian, but he just eats pizza, pasta, and cheese and looks like a piece of giant dough. He's not doing it right and I wouldn't advocate anyone to follow his example. However, now is the best time to become a vegetarian or vegan. There are so many more non-animal protein sources available, it's unbelievable. It's not the 1960s anymore where you had to eat soy gruel.

I'm normally a vegetarian but I've actually gone vegan for lent, not religious, just a suitable date range.

I'm doing it for the perspective you get. It's real interesting to see much how dairy is in the products you buy.

Also you generally expose yourself to different products, which tend to carry over to once you stop.

I'd recommend trying it.

One of my kids is lactose intolerant.... then I discovered that milk powder is in SO many products as it's a cheap way to add a rich flavour to foods.

The net result is that through a genetic accident (the kid is half chinese half european and it's likely the intolerance comes from the chinese side) we all eat more healthily.

Referring to the article: When you have to be more careful about what you eat you tend to have to make more of your own food and, for me at least, the act of making food suppresses my appetite resulting in me eating less. I think this is because it effectively lengthens the time my brain is in 'eating' mode and it feels satiated after less food. I basically made that up though but I'm happy to live with that.

I wouldn't say I am any healthier but I have maintained my current level of unhealthiness with less food :)

Would be MUCH more useful if he detailed what he ate, even if it was just one or two days worth of meals.

I mean, there's a ton of good food out there, especially if you look in vegan friendly ethnic cuisine (Indian especially), but I'd rather get a menu than a "I felt ill after meat" diatribe.