Category Archives: Food and diet

The Cholesterol Myths

Many years ago I read The Cholesterol Myths, published in 2000, by Uffe Ravnskov. You can find Uffe’s work here: The Cholesterol Myths.

It was a stunning analysis that changed my food habits, and which I know has made me healthier and more energetic. I found friends, with whom I discussed the diet changes that I had made, skeptical because of the well-promoted, supposed link of saturated fat & cholesterol to cardiovascular disease.

Now I see the benefits of saturated fats may be about to become a more mainstream view: Butter and cheese better than trans-fat margarines, says heart specialist


Just when I thought I could put “Healthy” on my own Marmalade jars

How could this ruling come about?

Obesity experts appalled by EU move to approve health claim for fructose
But the EU has now ruled that food and drink manufacturers can claim their sweetened products are healthier if they replace more than 30% of the glucose and sucrose they contain with fructose

I read that a can of sugar sweetened soft drink has 39 g of sugar (sucrose). This is 19.5 g glucose, and 19.5 g fructose after ingestion. If a third of the sugar is replaced by fructose we get consumption of 13 g glucose and 26 g fructose. The guide for what fructose we can cope with each day is 15 to 25 g, so we are already over that limit with just one drink.

The suggestion is that this is healthier because whereas glucose raises the blood insulin level, fructose does not. Here is a good summary of the problem:

Sugar Is a Poison, Says UCSF Obesity Expert

You don’t fix a problem by switching off the warning light. People will be attracted to the “Contains healthy fruit sugar!” on the pack.

My prediction:
Fructose is processed by the liver to fat (triglyceride). There’s a host of bad consequences, but one I will single out. On a blood test the fructose drinkers will be told they have a bad lipid profile and will be put on statins. The statins will block the liver from making cholesterol, which is needed among other things as a component in the lipoproteins that transport fats to where they are needed or stored. Some fat from fructose will stay in the liver and the person will develop non-alcoholic fatty liver disease. If the fructose is added to alcoholic drinks that will be a double liver problem as alcohol follows the same pathway, but at least you know you drank it. In 10 years there will be a lot of people needing a liver transplant.

As in Alice in Wonderland, “When I use a word,”  Humpty Dumpty said, in rather a scornful tone, “it means just what I choose it to mean—neither more nor less.” So, healthy has just been redefined.

Making marmalade

Several years ago I had a common blood test that showed that the HbA1c level was near the upper limit of what is currently regarded as acceptable. At that point I realized that I knew little about insulin and its function. I remedied that on a journey which eventually covered both nutrition and cell biology. On the way I discovered research by Robert Lustig, who now has a viral video, Sugar: The Bitter Truth, on YouTube. I had read the book Pure, White and Deadly published decades ago by nutritionist John Yudkin, and Robert Lustig was making the same point more forcefully. I had found most marmalade too sweet anyway so I experimented.

The recipe uses a 850 g can of cut Seville oranges. The can says to use 1.8 Kg of sugar. I reduced that to 1.3 Kg. Then noting that Lustig points out the different and less benign metabolism of fructose compared with glucose (especially for us non-athletic types), decided to try using glucose instead of sugar. This did not produce marmalade as we know it but some cloudy syrup.

The best result of experiments is:

850 g can of prepared Seville oranges. This can be fresh Seville oranges when available but then add pectin.
400 g water
650 g sugar
650 g dextrose

Boil for 10 to 15 minutes. You have to check for setting as it explains on the can, though I now keep all factors, quantities & heat, the same and find I don’t need to test.

This mix will give you about 1.5 g of fructose in two teaspoons of marmalade, and has the right bitter edge that is the point of having this conserve. If we go by what we used to consume before the days of cheap bulk sugar it looks like we had up to 15 g fructose a day; so this marmalade gives you space for other fruits. Friends to whom I have given a jar say they like it and don’t refuse more.

Newton’s law of cooling

I have been making yogurt since 1965. After initial trial with a yogurt making kit the method became simplified into equal quantities of evaporated milk and boiling water poured into jars that then have a spoonful of the last batch of yogurt added. These jars then go into a polystyrene milk-bottle keep-cool container that I got in 1962 as an offer with Kellogg’s cornflakes! Left overnight there is perfect yogurt in the morning. There is some pleasure in still using this battered polystyrene box, up-cycling it in current jargon, for almost 50 years – technology you can trust.

The past few years I have had some mild allergy to “standard” milk that I don’t have with organic milk. Now I am making yogurt with organic milk that needs heating to 82C to kill bacteria and prepare the milk protein to help setting, and then cooling to 43C before adding some of the last batch of yogurt.

The cooling takes over an hour and to start with I kept going to check because the final temperature is critical. Then I thought that I would make use of Newton’s rule-of-thumb about bodies cooling in still air. It was a delight to see the near linear plot of log(temperature difference) against time. This I now use by taking the starting temperature and one other reading at a later time that an excel spreadsheet then turns the time I need to go and add the yogurt – ping.

The temperatures are measured with an IR thermometer that I got to help with research on house insulation. The measurements of temperature and time are rough – same eyes reading both and jotting down – but fit for purpose.

Temperature vs time
Cooling of the yogurt jar

Final points: The top and bottom temperatures of the jar are different and half-way up the jar gives a reasonable average. The milk in the jar is hotter than the temperature on the outside, in my case by about 2C. I add one dessert-spoon of yogurt and that cools the milk by about 1.5C . The final milk temperature I aim for is 43C, so 43C on the outside is just about right.

At last into that courtesy-of-Kellogg’s 1962 insulating box.

Probably all this is over done, but it is irresistable to let a bit of our skills affect everything we do.

Food, nutrition and diet

On a whim, last year, I started to look into what is known about insulin. I mentioned this to my GP one day who then said, “You are not diabetic are you?”. He persuaded me to have an A1C that after some delay, as a typical always-ignore-medical-problems male, I booked myself in for. I was within the bounds but at the higher end for blood glucose level. This turned the insulin search into one biased towards practical understanding of the effects of food on insulin and fat. The starting point was a UCSD-TV lecture by Robert Lustig on childhood obesity that you can find on (with other fascinating lectures). I have forgotten how I came across that early but it was a great inspiration. I was stunned by the discussion of glucose & fructose metabolism.

I had a wonderful teacher of chemistry at school, Bill Waterhouse, who spent extra hours with me to give me a good start with organic chemistry and later he told me he thought that I should have done a degree in biochemistry, but that was not the route I took. [I mention my teachers from decades ago in part to remember them but also to flag the importance of this profession for our human future.] Over the years I have picked up some biochemistry and physiology partly from interest and partly to help in projects I have been involved with but I always accepted the experts without any delving into details. So I thought fructose was good and fats bad because that was what the government scientists advised.

I saw a lecture by Michael Pollan on and was thereby introduced to his writings. He was discussing his book, In Defence of Food. He gave a summary of its important conclusion: “Eat food. Not too much. Mostly plants.” and commented that with that you did not really need to read the book.  Of course reading the book then becomes irresistible. There is a rich diet in its 208 small pages.
The most important insight for me was that the recent rise of the industrially produced diet of heavily processed ingredients has a big danger. We have evolved over hundreds of thousands of years to choose the mix and quantity of the food we eat. There was a big change already in going from hunter-gatherer to pastoral agriculture that Pollan suggests we have not yet fully adapted too, but we will leave that aside. Of the foods that were available up to about 1900 we knew if they were good or bad for us without consulting a nutritionist, otherwise humanity would have ceased to exist. 100 years on and we can manufacture food for which we can no longer tell that. It may smell and look and taste like good food, but it could have no real food value for us, it could be harmful. Some is harmful, not with deliberate intent of the manufacturers because at the very least they don’t want to kill their revenue source, as it leads to obesity and its consequences such as diabetes and cancer and joint problems. Sugar especially was just a small part of some produce, now the world is awash with sugar in almost every processed food; with its enhancement – high fructose corn syrup. We do not have a gut way to decide on these foods, they seem fine by our evolved criteria but our built-in instruments are deceived.
We are focussed on acute disease that kills or disables fast, less so on chronic disease that takes decades to develop. This is not to say that there can be no input from scientific study but we need to be sure that it really does improve our food.