Kindle Notes & Highlights
by
Zoe Harcombe
Read between
June 5 - June 20, 2023
how can anyone who knows about nutrition put low fat and healthy diet in the same sentence?
fat supplies the most concentrated form of energy in our diets
Man would not be here today without the energy supplied by fat (predominantly from animals, but also from nuts) during evolution and particularly during the ice age and in regions of the earth where vegetation was not available.
fat cannot make us fat – only carbohydrate can do this. The glycerol backbone, which turns fat particles into a triglyceride (the form in which adipose tissue is stored), is produced in the presence of glucose and insulin – the environment created following the consumption of carbohydrate.
In this carbohydrate consuming/calorie avoiding world, we have lost the awareness of the palatability and unique satiety of fat.
We know that carbohydrate (via insulin) facilitates the storage of fat. We know that stored carbohydrate, glycogen, is turned into fat if not needed by the body within approximately 24 hours.
I cannot find one meat on the planet with more saturated than unsaturated fat. Surely no sensible person can really believe that, of the small part of their steak that is fat, 45% of this is trying to kill them and 51% is trying to save them – no doubt helped by the 4% polyunsaturated fat backup?
Nature puts macronutrients, let alone fat, in real foods in quite an interesting way. Protein is in virtually everything from lettuce to lamb. Other foods then tend to fall into ‘things from faces’ which are fat/proteins or ‘things from trees and the ground’, which are carbohydrate/proteins. The former group comprises zero carbohydrate foods (meat, fish), virtually zero carbohydrate foods (eggs) and low carbohydrate foods (dairy products). The latter group includes fruit, vegetables and whole grains (remember this is all about real food as nature delivers it, not processed food as
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Nature puts fat in real foods in a similarly interesting way. In 100 grams of pork chop (USDA reference – pork chop, boneless, raw, lean and fat), there is no carbohydrate, 21 grams of protein and 4.2 grams of fat. The rest is water (75%). Of the 4.2 grams of fat, 1.5 grams are saturated and 2.7 grams are unsaturated.
We are told to eat oily fish – mackerel is one of the oiliest fishes and, of the 14 grams of fat per 100 grams of mackerel (much higher in fat overall than the common meats, pork and beef), 45% is monounsaturated and 27% is saturated (the rest is polyunsaturated fat, which is high in fish generally). So, 100 grams of the oily fish we are supposed to eat has more saturated fat than beef or pork.
First of all, we eat food, we don’t intravenously inject it.
saturated fat is solid at room temperature, let alone at fridge temperature, so there is no way it could be poured down a sink,
there is a pump mechanism around the body (the heart, blood and circulatory system) to ensure regular movement of nutrients in our blood stream to all parts of the body.
From there it goes into the stomach (the main area for food ‘short-term’ storage and digestion of protein and carbohydrate). Fat is not digested until it passes from the stomach into the small intestine (where almost all nutrients are absorbed) and, from there, it passes into the large intestine (the main function of which is to transport waste out of the body and to absorb water from the waste before it leaves).
chylomicrons are formed in the intestine, as a result of digestion, and chylomicrons are the transport mechanism for taking dietary fat (and cholesterol) from the digestive system into the blood stream and from there to the different parts of the body to do their vital work.
The chain length of fatty acids determines how they are transported out of the digestive system. If a fatty acid has fewer than 12 carbon atoms, it will “probably travel through the portal vein that connects directly to the liver. If the fatty acid is a more typical long-chain variety, it must be reformed into a triglyceride and enter circulation via the lymphatic system.”
The five longer chain saturated fats and the unsaturated fats are packaged into chylomicrons, released into the lymphatic system and they glide from there into the blood stream. So, our coconut oil has not been injected into our arteries. It has not gone into any arteries through any less invasive route. It has gone on a normal digestive process journey, probably taking a few hours for fat, still without going into an artery.
this means – the most common fat we found in the plaques was elaidic acid – that’s a trans fat. Every plaque sample contained linolelaidic acid – that’s a trans polyunsaturated fat. No mention of saturated fat whatsoever.
What we must do, however, is to stop calling these products saturated fats. The main macronutrient in the meat products analysed above is fat (primarily unsaturated fat), followed by carbohydrate and with protein a long way behind. Ice cream and the entire categories E, F and G are all primarily carbohydrates. The main fat in foods in categories E, F and G is invariably unsaturated fat. We can agree that they should be avoided/cut out altogether, but we need to advise this for the right reason. If there is any real meat, real egg, real milk etc in any of the above products, it will be the
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nature puts different fats in foods in the ‘right’ balance. Food manufacturers have artificially decided what the ratio should be – more likely determined by cost, taste, look and feel and so on.
Dairy products are highly nutritious and they are excellent sources of protein and the fat soluble vitamins, A and D particularly, and this means they need to be delivered in fat to be absorbed by the body. How sensible of nature to put fat soluble vitamins in fat and how stupid of humans to remove the fat and thereby the delivery mechanism.
The ultimate irony is that an entire industry, worth five billion dollars in the USA (2008) alone,[253] has been built on destroying the reputation of butter and then trying to reproduce the substance. Butter is mostly saturated fat, naturally solid at room temperature and it has a natural colour. The first part of the imitation process is to take liquid oils, usually cheap and low quality vegetable oils, and then turn them into solid fats in some way. Hydrogenation is one way, increasingly less acceptable nowadays but still done. In this process the oils are heated and pressurised and
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The substance at the end of this process is grey, smelly and lumpy, so it is bleached, deodorised and emulsifiers are added to smooth things over. The mandatory vitamins are added in at this stage because none could have survived that process. Finally, the stuff needs some colour to make it look edible, so, of course, the preferred colour is butter colour.
The processed spread is much cheaper, despite all the industrial operations needed. Real butter needs to come from a real animal and the best butter is hand churned. Checking my on line grocery store today, the cheapest butter that I can buy is nearly three times the price of the cheapest spread. The butter is sold in 250 gram packets. The spreads are sold in 500 gram, or one kilogram, tubs.
Carbohydrates are organic molecules in which carbon, hydrogen and oxygen are bonded together in the ratio Cx(H2O)y, where x and y are whole numbers that differ for different carbohydrates. The body will break down carbohydrates into their simplest form, which is carbon, hydrogen and oxygen in the ratio of 1:2:1 respectively.
Monosaccharides are also known as simple sugars and they contain one molecule
Disaccharides are composed of two monosaccharides i.e. two simple sugar molecules
Polysaccharides are composed of many molecules, as the pre-fix ‘poly’ suggests.
- Glycogen – is the form in which animals (including humans) store energy – in the liver and muscles in the body; - Starch – is the form in which plants store energy – as in grains, pulses, potatoes and root vegetables. The chemical formula for each of these is (C6H10O5)n – i.e. multiples of 6 carbon, 10 hydrogen and 5 oxygen combinations bonded together.
The indigestible forms of polysaccharides are collectively called fibre. Fibre contains sugars linked by bonds, which cannot be broken down by human enzymes, and are therefore deemed indigestible. There are two forms of fibre: 1) Insoluble fibre (which does not dissolve in water). This contains cellulose, hemicellulose and lignin.
Soluble fibre (which dissolves, or swells, in water). This contains pectins, mucilages, and gums. They are not broken down by human enzymes, but instead can be fermented by bacteria in the large intestine. Pectin can be found in apples, strawberries and carrots.
Since fibre is not digestible, it is not considered to provide energy (calories) to the body.
In any definition of carbohydrate, the most common word seen is “energy”. Carbohydrate provides readily available energy for the human body.
The nutritional debate, as to whether or not humans need carbohydrate, centres on vitamin C. All other vitamins and minerals are found in animal foods (and some, like vitamin B12, are found only in animal foods).
1) Our ancestors lived for 1,200 generations through the ice age, and in many areas of the earth, with no consistent access to carbohydrate, if any at all. There are populations today that live solely on animal foods.
Stefansson found that vitamin C could be obtained from raw meat
It is likely that meat needs to be raw to provide vitamin C, as vitamin C is destroyed in cooking (the same applies in cooking vegetables and/or fruit, however, and this is not noted in our ‘five-a-day’ mantra).
Sugar, as the most refined carbohydrate of all, requires vitamins, such as B and C, and minerals for its digestion and metabolism and yet provides none in return. It follows that our need for vitamin C would be reduced if we avoided these substances
We can say with confidence that, even if we need a few berries to provide vitamin C in our diets, especially in the absence of food like raw whale meat, we absolutely do not need refined carbohydrates at all
we either don’t need, or need very little, of the one macronutrient that we are currently advised to ensure forms the vast majority of our diet – carbohydrate.
the body breaks down carbohydrates into their simplest form. This is done in the presence of water (H2O).
We started off with 342 units of, let’s say, maltose. We added 18 units of water from the body and we ended up with two units of glucose at 180 each – equals 360 units. So, our original 342 units of carbohydrate ended up as 360 units of carbohydrate after being broken down by the body. This added 5% in mass and, therefore, if we started with 100 grams of carbohydrate, we end up with 105 grams of carbohydrate. If we assume that carbohydrates have four calories per gram, we started off with 400 calories of carbohydrate (maltose) and ended up with 420 calories of carbohydrate (glucose).
This time we started off with 162 units of, say, starch and we ended up with 180 units of glucose and we therefore added 11% in mass. In this scenario, we started with 100 grams of starch and 400 calories and we ended up with 444 calories. Hopefully even the most ardent calorie counters are starting to doubt the wisdom of basing their meals on starchy foods and/or counting calories.
a rule of thumb for the body’s daily requirement for protein is one gram per one kilogram of body weight.
Both the protein and the fat in the tuna represent calories with ‘a job to do’ within the body – not merely calories that supply energy, for which I may or may not have a requirement that day. Carbohydrates do not have these additional and vital roles – they merely supply energy.
Carbohydrate digestion starts in the mouth. Salivary amylase is an enzyme found in human saliva (also known as ptyalin) and this mixes with the food as we chew and starts the process by which starchy foods are broken down into simpler saccharides. Starch breaks down into maltose
For the purposes of digestion, the body does not know the difference between glucose as the result of, say, sucrose intake (which breaks down into one molecule of fructose and one of glucose) and glucose produced by starch digestion.
the way in which energy is being transformed continually in the body – not least with 50,000 enzymes with roles to play;
The end goal of the energy cycle is a substance called ATP. ATP stands for Adenosine Tri-Phosphate. It is an organic compound made up of adenosine (an adenine ring and a ribose sugar) and three phosphate groups, hence, the name. ATP contains a large amount of chemical energy stored in its high-energy phosphate bonds. It releases energy when it is broken down into ADP (Adenosine Di-Phosphate). The energy is used for many metabolic processes. Hence, ATP is considered as the universal energy currency for metabolism. Plants make ATP during photosynthesis. Humans make ATP by breaking down molecules
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1) Glycolysis – this takes place in the cytoplasm (the cytoplasm consists of all of the contents outside the nucleus, but within the membrane, of a cell) and the goal of glycolysis is to break glucose down into two pyruvates, also known as pyruvic acid
