Saturday 23 February 2013

can vegetarianism be unhealthy?

There was a very interesting article in the Independent newspaper on Thursday (21/02/13) titled From vegetarian to confirmed carnivore where John Nicholson stated that when he was eating a low-fat wholefood vegan diet he felt ill. He became obese and had irritable bowel syndrome (IBS), diarrhea, fatigue and headaches. His partner, who shared his way of eating, had depression and mood swings.

They decided to ditch the wheat, rice and potatoes and eat lots of meat, butter, cream, lard and goose fat. He felt better straight away and lost lots of weight. His cholesterol levels went down. This seems on the face of it to contradict everything that I have been saying on this blog, about people eating less meat and more starchy foods and vegetables. However, I think I can understand what is happening here.

John seems to have gone from one extreme to another. From veganism to eating lots of meat and animal fat. When people make radical changes in the way that they eat, often excluding whole food groups, they often gain weight or lose weight without trying. They may be getting more calories or fewer without knowing.

The placebo effect might explain some of why John started to feel a lot better straight away. I don't want to dismiss what he says though. It is possible that John had an iron or zinc deficiency which was rectified as soon as he started eating meat, especially as his first meat was ox liver. It might even be that he wasn't getting enough protein, although it's not that difficult to get enought protein on a vegan diet. Another possibility is that he was suffering from an allergy to wheat.

If he had been eating soya products, that might have caused problems. Soya contains phytic acid which reduces our ability to absorb iron and zinc and trypsin inhibitors which reduce our ability to digest protein. This might not be a problem with traditional foods like miso, tofu or tempeh, but might be more of a problem with other ways of eating soya.

John seems to have moved to what is in effect the Atkins diet. In the Atkins diet people do not try to control calories but eat as much meat and animal fat as they like. The main thing they are trying to avoid is carbohydrate. It is a low-carbohydrate diet. When you digest carbohydrate, glucose enters the bloodstream. If you have too much glucose in your bloodstream your body needs to remove the excess or it will cause problems. Your pancreas secretes the hormone insulin which tells the body to remove some glucose.

In most people insulin and glucose levels rise and fall. Too much of this causes problems though. Obesity is only one problem that can happen when we have big rises and falls of insulin and glucose. Obesity can give rise to other problems. It is now recognised that this is one of the biggest causes of ill health.

People on the Atkins diet tend not to eat vast numbers of calories because the diet is less varied than a normal diet. They can easily get bored with it or even a bit nauseous contemplating the prospect of yet more meat and fat. It is often said that people crave fat, but a lot of the fat we eat is hidden. If you eat a slice of cake, you don't realise how much fat is in it because the flavour is masked by sugar or something acidic such as lemon. We eat so much fat not because we love it so much but because we don't know it is there.

I don't have a problem with the Atkins diet. It does seem to work at helping people to slim. I do wonder about the long-term effects of staying on the Atkins diet though. I'm not just worried about heart disease and strokes, reducing protein has been linked to increased longevity.

I wonder if it would work just as well if instead of meat they ate fish, and instead of eating butter and lard they ate avocados and olive oil. In Crete people traditionally got lots of their calories from olive oil and far from harming them it seems to have contributed to health and long life.

Also, there are some forms of carbohydrate that are better than others at not flooding your bloodstream with glucose. Starch is better than sugar, and the amylopectin form of starch is better than the amylose form. You can measure the effect that a food has on your blood glucose levels. A low glycemic index (GI) is better than a high glycemic index. Long-grain rice is better than short-grain rice. Brown rice is better than white rice. Pasta and porridge are good too. If you eat some low GI forms of starch it won't have too bad an effect on your blood glucose levels.

Vegetables can seem to have a high GI but really they are mostly OK. Baked potatoes are not good though. So I shall continue to eat my long-grain rice and pasta, together with my pulses and vegetables. I do eat meat, cheese, fish and eggs sometimes but not every day. What John Nicholson has said in no way invalidates what I have stated on this blog about the problems of trying to feed everyone on the planet with lots of meat. We can't feed 7, 8 or 9 billion people with a diet high in meat.

A good point that John makes is that not everbody is the same. People vary as to what sort of foods they thrive on. I think it is likely that some people digest starch more readily than others. If so, they are less likely to thrive on a high starch diet even if it is low GI.

In case people are thinking that they can just add butter and cream to their normal foods and get away with it, it doesn't work like that. If you want to eat lots of meat and fat and lose weight then you would have to go on an extremely low-carbohydrate diet, or you will just put on weight.

Friday 22 February 2013

reducing meat consumption

In this week's New Scientist magazine (23/02/13 page 5) it tells us that the UN Environment Programme has revealed that 80% of the fertiliser use in farming globally is for meat production. Pastures are fertilised to boost grass production and for fodder crops. I guess that by 'fodder crops' they mean maize and soya, and also wheat and barley (I'm not sure if soya requires nitrogen fertiliser, as a legume perhaps it does not).

Half of the fertiliser put onto the land isn't used by the crops. It runs off the land into the rivers and seas and causes environmental damage. The solution, according to the authors is for fertiliser to be used better and for us all to eat less meat.

This figure of 80% is a surprise, and it fits in with what we already know about how much of the crops grown - mainly maize and soya - are fed to farm animals. It's also mentioned in the Guardian article about this UN report (18/02/13).

In the Guardian article it says that the authors of the report are not suggesting that we give up eating meat. They are suggesting we become demitarians - eating half as much meat as we are used to. I agree with this, but there are a couple of points I'm not so sure about.

The lead author, Professor Mark Sutton, says we should replace most of the meat on our plates with vegetables. Meat provides us with protein and calories, and although we could do with less of both of these, we're probably going to need something to make up for the shortfall if we replace meat with carrots, broccoli etc. Vegetables don't have much in the way of protein or calories, but pulses are a cheap form of protein (and have some calories) and grain in the form of rice and pasta are the cheapest form of calories (and have some protein).

One of the problems in asking people to eat less meat (or less junk food) is that they think they're going to be expected to live off celery and lettuce. They don't have to, they can have tasty rice and pasta dishes. Vegetables are thought of as too expensive for poorer people, which isn't true, but it's easy to see how rice and pasta are the cheapest foods, much cheaper than any form of meat.
Professor Sutton also says that people in poor countries should be 'allowed' to increase their consumption of animal protein. It is true that in some countries people don't get enough protein, although in other poorer countries people do get enough - it's just that they like the idea of eating more meat. I don't see why it has to be animal protein though. Since the UN changed it's official estimate of how much protein people need downwards in 1985 we've known that people don't need that much of it.

People who aren't getting enough protein are usually people who aren't getting enough food. If someone gets enought calories from rice they will be getting almost enough protein. It doesn't take much in the way of beans, peas or lentils to give someone both the quantity and quality of protein that they need. In Indonesia people were encouraged to eat less tempeh (a traditional food deriving from soya beans) and more chicken. I think that was wrong. Protein from tempeh or tofu, or beans or lentils, is just as good as animal protein. It's more efficient to convert soya beans into tempeh or tofu than into chicken and pork.

Professor Sutton says that chicken and pork are the meats that cause the least amount of environmental damage. "Chicken is one of the most efficient [meats] as it grows very quickly and you can collect the manure," he says. Chickens have one of the best conversion rates of grain and soya to meat. Better than pigs, so let's not encourage more pig keeping. I would expect eggs to be an even better way of getting cheap protein than chicken meat. Also, freshwater fish and things like crayfish are even better than chickens. Mammals and birds use up a lot of their calories in generating heat internally, so cold-blooded animals are even better converters of plant protein into animal protein.

So I agree with the principle of demitarianism, but there should be more emphasis on grains (like rice and pasta) and pulses. We shouldn't fall into the trap of thinking that food falls into a spectrum with affordable junk food at one end of the spectrum and unaffordable fruit and vegetables at the other end of the spectrum. Also, I don't think we should encourage the poorer countries of the world to produce more animal protein.

Saturday 16 February 2013

food mislabeling

Food mislabeling is an issue that's been in the news a lot recently. This post isn't about horse meat though. It's about something less important but it does say a lot about the attitude of retailers. Yesterday I went to Borough Market in London. I wanted to see what it looks like now all the building work has been completed. I also wanted to buy a few things, like blood oranges.

Blood oranges come from southern Italy and Spain and are available at some markets now. They have a different colour and taste from the usual oranges. There are different cultivars, the Moro being the best flavoured. There are several places in Borough Market where blood oranges are sold. The first one I came to didn't label the blood oranges on display with the name of the cultivar. I picked up two and asked the assistant at the till if she knew what the variety is. She didn't know.

The next place I went to I could see that the name on the box was Moro. This was the tiny lettering that the grower puts on the box that the fruit are transported in. Again, there was nothing that the seller put on his label to say what cultivar it is.

The third place I went to was the biggest of the fruit and vegetable sellers. It is called Turnips. There were a number of boxes of blood oranges, and they had placed on top of them a laminated information sheet. This sheet was all about the Moro cultivar. So I assumed they were all Moro. Until I looked on the box and it said Tarocco. So what are they, Moro or Tarocco? I think what they do is to put the same information sheet on their blood oranges, irrespective of what cultivar they are.

Bear in mind that what they say about Borough Market and similar places is that if you're not sure then you can ask the vendor and they will tell you all about the produce that they are selling. All the people working there were busy, but if I had asked I would probably have got the same response as at the first place.

It's not important if someone like me can't get my Moro blood oranges. In fact, I can get them, elsewhere. What is important is that even at somewhere like Borough Market they can't even be bothered to get their labeling right. I can't work out if they are stupid or if they think we are stupid. Another thing I don't like is when I ask for something, they tell me it's out of season, even when I know it is available elsewhere.

I've been getting my Moro blood oranges at 4 for £1 from Berwick Street market in Soho. So they're not some kind of expensive item that ordinary people can't afford.

I've got 3 more examples of casual labeling, all from Sainsbury's. A couple of years ago I bought a cheap camellia plant. It was labeled as the variety Debbie, a variety that I am familiar with and I like the form of it's flowers. It's in flower now, for the first time, but it's definitely not Debbie. It was quite cheap to buy, and if they had said that it could be any variety, or if they said it was had pink flowers, I might still have bought it. But I don't like being told that it is one thing and then finding it is something else.

I was in the bakery section of Sainsbury's recently and there were 4 round loaves in a basket. They all looked exactly the same, they all had the same packaging, but 2 were labeled 'sourdough' and 2 were labeled with a fancy French name that I didn't recognise. I think that they were just all the same.

In some of the bigger Sainsbury's they have a café. I like their filter coffee. But if I ask for filter coffee, one of 3 things happens. They either pour some coffee out of a vacuum flask. This seems to taste the best. Or they have a machine with a tap. Or they use a similar method as when they're making latte or cappuccino. I think this is technically called an Americano. I don't mind so much but I would like to know what I'm getting.
blood oranges