Back to black, CIAB, pharmaceutical drug deficiencies & nerds.

First, a song by someone who should be alive, but isn't...

The above video was inspired by a Facebook friend who had an accident with Schwarzkopf black hair dye and spent ages getting the stains off her skin. You know who you are!

I may have mentioned that nutrient deficiencies can adversely affect mental (and/or other) function. Nowadays, many people live on a diet of Crap-In-A-Bag (CIAB). There's just enough essential amino acids (EAAs), essential fatty acids (EFAs), minerals & vitamins to keep their bodies alive. However, Alive ≠ Working properly.

To compensate for one (or more) nutrient deficiencies, many people are prescribed one (or more) pharmaceutical drugs to tweak how their brains work e.g. fluoxetine, citalopram/escitalopram, venlafaxine, quetiapine, risperidone, valproate etc. There are no pharmaceutical drug deficiencies!

There are people who suffer from mental (and/or other) illnesses, despite having diets & lifestyles that provide sufficient amounts of all nutrients. This post isn't about them. There are people who suffer from depression due to traumatic & inescapable events/situations. This post isn't about them, either.

Finally, nerds! We nerds love to compile information. For an interesting interview with a top compiler of useful information, see Examine's Supplement Goals Reference Guide.

For an excellent article with a mere 148 references, see Why Calories Count. To sum up:-

Where body weight is concerned, calories count (but don't bother trying to count them).
Where body composition is concerned, partitioning counts.
Where health is concerned, macronutrient ratios, EFAs, minerals, vitamins & lifestyles count.

N.B. Poor health can adversely affect body weight and/or body composition, by increasing appetite and/or by adversely affecting partitioning.

Continued on Chow on chow, Parkinson's Law, two ways of doing something, and love.

Completing the trine: Which are the safest fats?

First, watch this video by Chris Masterjohn.

Diets very high in pufas (polyunsaturates) are not beneficial to heart health or longevity. Flora? No thanks!

Here's a chart. The beige & grey bars represent pufas (omega-6 & omega-3).

Comparison of dietary fats

The yellow bars represent monounsaturates and the orangey-red bars represent saturates. I consider these to be harmless, as long as you don't go mad and eat them in such large amounts that you gain weight.

Bearing in mind the information in the video, plus the information in Fats: Spawn of Satan or Dogs' Doodads? , I use only fats from the bottom 6 for cooking (olive oil and butter, actually).

Flaxseed oil can be used as an omega-3 supplement for vegetarian/vegan women, as omega-3 pufas are as rare as rocking-horse poo in most foods (apart from oily fish).

Non-vegetarian/vegan people can get their long-chain omega-3 pufas (EPA & DHA) from oily fish. As vegetarian/vegan men barely produce any DHA from the omega-3 in flaxseed oil, they should get it from algal DHA supplements. See Extremely Limited Synthesis of Long Chain Polyunsaturates in Adults: Implications for their Dietary Essentiality and use as Supplements.

Respiratory Exchange Ratio (RER) explained.

Science!

What the heck is this?

RER has been mentioned a few times on this blog. By measuring the rate of CO2 exhaled and the rate of O2 inhaled, it's possible to work out how many kcals/min the body is generating from food at any instant and from what fuel mixture.

An RER of 0.700 means that 100% of energy is being generated from fat.
An RER of 1.000 means that 100% of energy is being generated from carbohydrate aerobically.
An RER of >1.000 means that 100% of energy is being generated from carbohydrate, some aerobically and some anaerobically.

How does this work? Fats are an ester of fatty acids + glycerol. Acid + Alcohol = Ester + Water.

Saturated fatty acids (the easiest type to calculate) have the generic formula CH3(CH2)nCOOH, where n can be from 0 to 16. Here are some saturated fatty acids and their n values:- Acetic (0), Propionic (1), Butyric (2), Lauric (10), Myristic (12), Palmitic (14) and Stearic (16). The total number of carbon atoms in each fatty acid is n+2. Stearic acid is mostly a load of CH2s, so lets approximate fat to n(CH2).

n(CH2) + 3/2n(O2) = n(CO2) + n(H2O) + Heat. The ratio of CO2 to O2 is 2/3, so RER = 0.666.

As fats contain things other than CH2 (e.g. glycerol CH2OHCHOHCH2OH), this raises RER to 0.700. Burning protein gives an RER = 0.800.

Carbohydrates have the generic formula n(CH2O), where n = 6 for glucose.

n(CH2O) + n(O2) = n(CO2) + n(H2O) + Heat. The ratio of CO2 to O2 is 1.000, so RER = 1.000.

So how on earth can Eskimos have an RER = 0.600? I have a theory. When hydrogen is oxidised, water only is produced. There is no CO2, so RER = 0.000. Therefore, if some hydrogen was being burned (by gut bacteria, say), this could result in RER falling below 0.700. Maybe...

Metabolic flexibility - do you have it?

I'm not quite sure what the picture below means (I need to do a spot of reading!).

Metabolic flexibility "bowl" and "Adaptability envelope"

While replying to Kade Storm this morning, it suddenly occurred to me that the Eskimos have an unusual ability. RER (a.k.a. RQ) normally varies from 0.7 (100% fat-burning) to 1.0 (100% carb-burning aerobically) to >1.0 (100% carb-burning, some anaerobically). Eskimos manage to get an RER of 0.600 *Mind blown.*

One theory that comes to mind is BAT. As Eskimos live in a very cold environment, it's possible that this has resulted in them having a large amount of BAT. BAT is very metabolically-active and turns ATP into heat via UCPs.

Nowadays, first-world people don't live in a cold environment (unless they're old and/or poor), so we don't have much BAT after infancy. Naturally-skinny people may be that way due to having more BAT. They seem to be able to eat whatever and as much as they want without getting fat. I would like to scratch their eyes out!

Everyone is Different, Part 3.

Cont'd from Everyone is Different, Part 2.

Hat-tip to Bill Lagakos, whose article Missing: 300 kilocalories reminded me of the following graphic from Effects of Dietary Composition During Weight Loss Maintenance: A Controlled Feeding Study.

Lo and behold, even when subjects are bribed to stick to the diets that they are provided with, the effect of eating those diets varies hugely.

So, people like ItsTheWoo and Petro Dobromylskyj (yes, I have to copy and paste the name from his site every freakin' time!) rave about how awful carbs are, while people like Go Kaleo and Matt Stone rave about how awesome carbs are.

Everyone is different for a number of reasons, some of which are unchangeable and some of which are changeable. We can't change our birth weight, what our mums ate when we were in the womb or the chemicals that we were exposed to in the past. We can't change our genes, but we can change the expression of our genes by changing diet, activity and even supplementation. See Influence of Vitamin D Status and Vitamin D₃ Supplementation on Genome Wide Expression of White Blood Cells: A Randomized Double-Blind Clinical Trial.

Everyone is Different, Part 2.

Cont'd from We are not all the same.

A long, long time ago...


I learned that Everyone is Different, thanks to a study by Julia H. Goedecke, Alan St Clair Gibson, Liesl Grobler, Malcolm Collins, Timothy D. Noakes and Estelle V. Lambert.

Well, stone the flamin' crows! Timothy D. Noakes' name just popped up in Alan Aragon's article 2013 NSCA Personal Trainers Conference: Looking Back at my Debate with Dr. Jeff Volek. Dr. Noakes has had problems with his blood glucose level and has adopted a very-low-carb/ketogenic diet.

What also caught my eye in Alan Aragon's article was (Note: TTE = Time To Exhaustion):-
"However, the authors’ conclusion is misleading since 2 of the 5 subjects experienced substantial drops in endurance capacity (48 and 51-minute declines in TTE, to be exact). One of the subjects had a freakishly high 84-minute increase in TTE, while the other increases were 3 and 30 minutes."

I expect that the subjects with 84 and 30 minute increases in TTE would be praising ketogenic diets, whereas the subjects with 48 and 51 minute declines in TTE would be cursing them and the subject with 3 minutes increase would be "Meh". Vive la difference!

Also note that sprint capability...remained constrained during the period of carbohydrate restriction. As mentioned in It's all in a day's work (as measured in Joules), exercise above a certain intensity (~85%VO2max) burns significant amounts of carbs, no matter how fat-adapted someone is.

Cont'd on Everyone is Different, Part 3.

On burning, storing and recomposing.

Burning

I couldn't resist!


On my adventures around the interwebs, I've noticed the following:- "Humans aren't Calorimeters. Therefore calories are irrelevant to humans." While I agree with the first sentence, I don't agree with the second one.

Calorimeters burn (oxidise) foods at high temperatures with a flame using oxygen, which produces carbon dioxide, water (depending on what's being burned) and heat energy.

Humans burn (oxidise) foods at 37ºC with enzymes , charge transporters etc using oxygen, which produces carbon dioxide, water (depending on what's being burned), mechanical energy and heat energy.

As both oxygen and carbon dioxide are gases, these can be measured by respiratory gas analysis to establish the rate of burning and what's being burned at any instant. See It's all in a day's work (as measured in Joules). When resting, burning occurs at a rate of ~1kcal/minute and as it's measured while fasted, ~0.11g/min of fat is burned and ~0.01g/min of carbs is burned. Also note that a lot of mechanical energy can be produced, which can increase the rate of burning by a factor of seventeen.

In conclusion, humans burn (oxidise) foods, though not with a flame and they can produce mechanical energy in addition to heat energy. The rate of burning and what's being burned at any instant can be measured.

Storing

When we eat food, it's digested and absorbed. As a digested meal is absorbed, it appears in the blood as glucose, triglycerides and amino acids. These then disappear from the blood due to burning and storage. See Extended effects of evening meal carbohydrate-to-fat ratio on fasting and postprandial substrate metabolism.

Figure 1 shows the effects of a 100g Oral Glucose load or a 40g Oral Fat load on blood glucose level over a period of 360 minutes. Note that subjects are resting during the 360 minutes. As the 100g Oral Glucose load produces a large blood insulin response (See Figure 2), fat-burning temporarily stops. Therefore, the ~1kcal/minute resting burning rate is derived from carbs. Therefore, the carb-burning rate is ~0.25g/min. At this rate, it would take ~400 minutes to burn 100g of glucose. However, it takes ~180 minutes for blood glucose level to fall from maximum to minimum. Therefore, some of the glucose from the Oral Glucose load is stored (mostly as glycogen in muscles and liver).

Figure 3B shows the effects of a 100g Oral Glucose load or a 40g Oral Fat load on blood triglyceride (fat) level over a period of 360 minutes. Note that subjects are resting during the 360 minutes. As the 40g Oral Fat load produces no significant blood insulin response (See Figure 2), fat-burning is unaffected. Therefore, the fat-burning rate is ~0.11g/min. At this rate, it would take ~364 minutes to burn 40g of fat. However, it takes 180 to 240 minutes for blood triglyceride (fat) level to fall from maximum to minimum. Therefore, some of the fat from the Oral Fat load is stored (as fat in adipocytes) even though there is no significant blood insulin response.

Therefore there are times when stuff is stored and there are other times when stuff is withdrawn from stores.

Recomposing

After doing intense exercise e.g. sprinting, resistance training with weights etc, muscles become very sensitive to insulin. Therefore, if intense exercise is done just before stuff is stored, stuff (amino acids and glucose) is preferentially stored in muscles rather than in adipocytes. This increases muscle mass relative to fat mass.

If non-intense exercise is done at times when stuff is withdrawn from stores, this maximises the amount of fat withdrawn from adipocytes and minimises the amount of stuff (amino acids) withdrawn from muscles. This decreases fat mass relative to muscle mass.

It's therefore possible to increase muscle mass at some times and decrease fat mass at other times while keeping overall mass relatively constant i.e. it's possible to gain muscle and lose body-fat without being in an overall caloric deficit. See Body Recomposition.

Reasons to get off low-fat diets...

Part 1. Increased risk of Coronary Heart Disease due to a lack of gamma-tocopherol in the diet. See Antioxidant state and mortality from coronary heart disease in Lithuanian and Swedish men: concomitant cross sectional study of men aged 50.

See 300 foods highest in Gamma Tocopherol per 100g serving. Low-fat dieters are discouraged from eating foods high in fat. There is no gamma-tocopherol in most Vitamin E supplements. There is gamma-tocopherol in nuts & seeds. Only use Vitamin E supplements that contain mixed tocopherols.

Ditto for beta-carotene, found in coloured veggies and poorly absorbed without dietary fat.
Ditto for lycopene, found in tomatoes and poorly absorbed without dietary fat.


Part 2. Increased risk of tooth decay due to a lack of Vitamin K2. If you listen to Denise Minger's talk, starting at 8 minutes in, she discusses her poor oral health at a young age brought on by a lack of Vitamin K2. Richard Nikoley also discusses the effect of Vitamin K2 on his oral health.

See Vitamin K.


Part 3. Increased risk of gallbladder disease when losing weight. This applies to people (particularly Fair Fat Females in their Forties) who are losing weight rapidly, as this concentrates cholesterol in their bile. I find it rather odd that some people are obsessed with doing exercise, but they fail to exercise their gallbladders by eating at least 5 grams of fat in a meal.

See The Protein-Sparing Modified Fast (PSMF).

Oh no, not again!

Today's title is a quote from Douglas Adams' "The Hitchhiker's Guide to the Galaxy".



There seems to be a lot of hysteria & worry around the Internet.

Oh, noes! They took away her lunch-box (they didn't)! Her lunch-box! That's crap!

Oh, noes! They made her eat chicken nuggets (they didn't)! Chicken nuggets! That's crap!

Oh, noes! They made her eat a portion of grain! A portion of grain! That's crap!

Oh, noes! They wanted to give her a carton of skimmed milk! Skimmed milk! That's crap!

Oh, noes! They wanted to give her a carton of chocolate milk! Chocolate milk! That's crap!

Is there too much fat in this Guacamole?

Is there too much omega-6 in this pork?

Is there too much BPA in this bottled water?

And so on...

Firstly, chicken nuggets, grains, skimmed milk and chocolate milk are not crap. They're not perfect, but they're far better than chocolate/candy bars and fizzy drinks.

Schools act in loco parentis, so they are not going to feed the children crap. USDA guidelines are nowhere near perfect, but children who aren't humongously fat are metabolically-flexible. Therefore, whether they eat carbohydrates or fats, their bodies will burn them. If a child has been diagnosed with Coeliac disease, they won't be given gluten grains (unless the school wants to get sued).

Eat some carbs, dammit. See Why I Ditched Low Carb.

To quote from The Hitchhiker's Guide to the Galaxy again, DON'T PANIC! The dose makes the poison. Dietary fructose is used by the liver to make blood glucose to run red blood cells & the brain. A non-keto-adapted brain uses ~140g/day of glucose. Therefore, in the absence of any other dietary carbohydrates, a child could eat 100g/day of fructose, or 200g/day of sucrose without harm. Obviously, other carbohydrates are being eaten, so the amount of fructose that can be eaten without harm is probably ~50g/day, or ~100g/day of sucrose, or ~90g/day of HFCS55.

Warning, irony alert. So, light up a large spliff and chill a bit! Here's a song to help.



EDIT: Worrying about "X" may be worse for you than "X" itself, due to the adverse effect of chronically-elevated cortisol.

Food Combining: What's THAT all about?

Some people believe in food combining, as per The Hay Diet i.e. don't eat protein with carbohydrate as protein needs acid conditions to digest and carbohydrate needs alkaline conditions to digest. This theory assumes that the human digestion system is like a big barrel where all foods get digested at the same time. This isn't the case.

The following is cribbed (with edits) from the bodybuilding.com message board (you didn't think I wrote all this, did ya?)

DIGESTION 101

The order you eat foods in does not make a difference to how they are digested. Once foods hit your stomach, the peristaltic motion (that is - the muscles in your stomach wall contracting) mix it all together regardless. In addition, the different enzymes that are released are released regardless of the order that you eat your food.

In your stomach:-
The presence of food in your stomach stimulates:-

1) Gastrin - this is what is responsible for the eventual release of Hydrochloric Acid (HCl) - stomach acid.
2) Pepsinogen - this is converted to pepsin by the acid in your stomach. Pepsin is important in the digestion of proteins.

In the small intestine:-
Once food hits the small intestine the pancreas and gall bladder are stimulated:-

1) Pancreas - It secretes many enzymes which help digest proteins, starches and triglycerides (fats).
2) Liver/gall-bladder - This is responsible for making and secreting bile. This is important in fat digestion. It is stimulated more when you eat fatty foods. The small intestine itself is also important, but it actually does not secrete anything. It acts to further digest the carbohydrates, proteins and fats, due to enzymes that are bound to the wall of the intestines, and then acts to absorb these things.

So - digestion occurs in two parts - the Luminal phase - which involves all of the enzymes that are secreted by the stomach, pancreas and liver. And the Membranous phase which is that which occurs because of the enzymes attached to the intestinal wall. It does not matter when you eat carbohydrates or proteins or fats during a meal, because the simple stimulus of food in your digestive tract will cause the secretion of the luminal enzymes (although as you increase your fat, you will stimulate more fat enzymes to be released).

Carbohydrates:-
Starches are the only type of carbohydrates to undergo luminal phase of digestion. This results from enzymes (called amylases) that are released from the pancreas. These act to break down the long starches into shorter polysaccharides (intermediate chains called dextrins). These are then cleaved again to form Disaccharides or trisaccharides (such as maltose or maltotriose). Sugars and the trisaccharides and disaccharides from the starches are then further digested in the Membranous phase. This involves enzymes (such as lactase - for the breakdown of lactose, sucrase for the digestion of sucrose and maltase for the breakdown of maltose) that are bound to the intestinal wall. So - these enzymes act on lactose, sucrose and the di and trisaccharides from the breakdown of starch to form glucose, galactose and fructose. These are then absorbed across the intestinal wall and enter the blood to go to the liver. The liver then takes up most of the glucose/galactose and all of the fructose and converts it into glycogen or fats while the rest stays in the blood for the rest of the body.

Proteins:-
These are broken down in a similar fashion as carbs. But - the enzymes involved in protein breakdown are secreted by the stomach (pepsin and chymosin) and the pancreas. There are lots of different enzymes involved in protein breakdown (because of the large variety of amino acids). So - digestion of proteins begins in the stomach with the secretion of HCl and pepsin which begin to cleave the long protein molecules. This then continues in the small intestines with the secretion of pancreatic enzymes. These smaller chains of amino acids (called peptides) are then either broken down by membranous phase enzymes on the intestine cells to form amino acids or are absorbed as dipeptides or tripeptides and then convert to simple amino acids by the cells. The amino acids are then released into the blood and are taken to the liver. In the liver, some of the amino acids go straight into circulation for the muscles, some are used directly for protein synthesis, but the rest are processed to enter the pathway of energy metabolism, carbohydrate formation or fatty acid formation.

Fats:-
This is a little different. Fat is harder to digest because it does not dissolve in the fluids in your gut. The digestion of fat is divided into four stages:-

1) Emulsification - This begins in the stomach and involves the warming and mixing of the fats. This breaks the fats into globules. The bile acids from the liver are then secreted into the intestines and make the fat droplets even smaller.
2) Hydrolysis - Enzymes from the pancreas (lipases) then act on the fats to form smaller molecules.
3) Micelle formation - These smaller molecules (free fatty acids, cholesterol, single chain fats etc) combine with bile to form tiny, droplets called micelles.
4) Absorption - The micelles then attach to the intestinal wall and all the components (except the bile) are then absorbed. These are then packaged (into things called chylomicrons) and secreted by the intestinal cells into tiny tubes in your intestinal wall called lacteals which take the fats to your heart, which then enters the back of your heart, which then pumps it around the body. These are then taken up by the liver or the fat cells. These processes in the intestine take a while to complete (depending on what you eat) and so eating one thing 5 minutes after the other will make no difference.

That said, there are certain combinations of food which are less desirable than others, but not for reasons of digestion.

Don't eat high-GI carbs together with whey, saturated, monounsaturated or omega-6 fats. High-GI carbs produce a large glucose and insulin response. Whey, saturated, monounsaturated and omega-6 fats magnify that insulin response. This results in unstable blood glucose levels and increased appetite. Virtually all junk foods are a combination of high-GI carbs and fats. The only time that an insulin spike is desirable is if you have just finished a workout. That particular insulin spike is obtained by swallowing whey with glucose and/or maltodextrin not usually accompanied by fat.

Don't eat fruit and protein foods at the same time. Fruit passes through the gut very quickly (possibly due to the fibre/fiber and simple sugar content stimulating peristalsis) and if eaten with or just after slow-digesting foods like meat or eggs, makes the protein pass through the small intestine faster than normal resulting in incomplete protein absorption and subsequent fermentation in the colon, producing smelly flatulence!

How to lose body-fat healthily.

Previous blog posts have been about Carbohydrates, Fats & Proteins. However, when you go shopping, you buy food. So this blog post is going to be about food. Updated!

1) If you're eating a high-carb diet, eat 6 small meals or 3 meals and 3 snacks per day to keep your blood glucose relatively stable. I used to believe that it also kept your metabolic rate high, but I now know this to be a myth. If you're the type of person who gets lowish blood glucose in the mornings (which may make you ravenously hungry and therefore highly likely to buy junk food when you're away from home), skipping breakfast is not advisable. If you're the type of person who isn't satisfied by small meals/snacks, a small number of large meals (Intermittent Fasting) is a better option.

2) Meals and snacks should contain proteins, fats and fibrous carbs.

3) Slow sugary/starchy carbs can be eaten in meals/snacks at breakfast and before/after workouts/exercise/intense activity. If/when you are sedentary, keep slow sugary/starchy carbs to a minimum. Keep fast sugary/starchy carbs to a minimum (except for the occasional treat or post-workout) as they can cause large fluctuations in blood glucose and insulin levels. The more intense exercise you do, the more slow sugary/starchy carbs you can eat.

4) Drink >1.5 litres of no-added-sugar watery drinks per day. If your urine is darker than straw, drink more. If you're weeing too often, drink less.

5) Balance your omega-6 and omega-3 essential fatty acids (EFAs) by eating about 100g of omega-3 rich oily fish (sild, sardines, pilchards, mackerel, herring, salmon, trout, fresh tuna etc) per day or supplement with fish oil capsules such that you get at least 2g of EPA+DHA per day. Please note that tinned tuna contains virtually zero omega-3 fat.
If you're vegetarian or vegan, eat 25g (women) or 50g ( men) of powdered linseeds (a.k.a. flaxseeds) per day with lots of fluids or supplement with flaxseed oil in bottles/capsules such that you get at least 10g (women) or 20g (men) of flaxseed oil per day.

6) Eat 2 to 3 portions of low-sugar fruits per day - preferably before meals/snacks. Minimise your consumption of high-sugar fruits.

Proteins are:- Meats, poultry, fish, eggs, cheese, Quorn, seeds, nuts, legumes (peas, beans & lentils).

Fibrous carbs are:- All vegetables that grow above ground level, bulbs (onions, leeks, garlic etc) and "vegetable" fruits (tomatoes, peppers, cucumbers/courgettes, aubergines, avocados, olives etc).

Slow sugary/starchy carbs are:- All-bran, no-added-sugar muesli, oats, sweet potatoes, lightly-boiled new potatoes eaten hot, cold or refrigerated, Basmati rice, non-overcooked legumes & root veggies, lumpy wholegrain rye breads, Burgen/Vogel's soya & linseed breads.

Fast sugary/starchy carbs are:- White wheat breads, wholemeal wheat breads, most breakfast cereals including Shredded Wheat, Weetabix, Cheerios, Grapenuts etc, sugar, sweets, chocolate, cakes, biscuits, cereal bars, sweetcorn, overcooked tubers e.g. jacket potatoes, overcooked root veggies, overcooked legumes e.g. baked beans.

High sugar fruits are:- Ripe & over-ripe bananas, grapes, pineapples, sweet apples, sweet pears, sultanas, raisins, currants and any dried fruits with added sugar.

Low sugar fruits are:- Berries, stone fruits, citrus, Granny Smith apples, Conference pears. Dried apple rings, apricots, pear halves, peach halves and prunes without added sugar are high in sugar but they release that sugar very slowly.

Fats are sats, monos and the EFAs mentioned above. Butter is high in sats and monos. Olive oil & spreads are high in monos. Sunflower/safflower/corn oils & spreads are very high in omega-6 EFAs - minimise your consumption of these. Don't fry or roast with high-EFA oils as they oxidise and convert into trans-fats too quickly. Meats contain sats, monos and some EFAs. Minimise your consumption of anything with the word "hydrogenated" in the ingredients list.

Some foods fall in-between categories like yellow bananas which are medium speed sugary/starchy carbs. Green bananas are slow carbs and black bananas are fast carbs.

Depending on your insulin sensitivity, speed of metabolism and exercise levels, you may get away with eating fast sugary/starchy carbs - you'll just have to "suck it and see".

One final bijou tip-ette:- Avoid walking down "dodgy" supermarket aisles (confectionery, cereals, booze, fizzy drinks) as "What the eye don't see, the heart don't grieve over".

Happy New Year folks!

Cont'd on How to lose body-fat healthily, Part 2.

Fats: Spawn of Satan or Dogs' Doodads?

Fats get a lot of bad press in the media. There are so many adverts with "X% fat-free" or "only 1g of fat per Jaffa Cake" as if that's going to stop you from getting fat when you "om nom nom" your way through a whole box of the things!

Saturated fats are usually described as "bad" and polyunsaturates are usually described as "good". This is simplistic. Everything is bad in excess, even polyunsaturates. The thing about fats is that there are four basic types (saturates, monounsaturates, omega-6 polyunsaturates and omega-3 polyunsaturates) and they need to be consumed in roughly the right proportions for optimum health. Suffice it to say, the majority of people in the West do not eat them in anywhere near the right proportions. So, what exactly are fats?

Fats

Fats are an ester of glycerol and three fatty acids and are also known as triglycerides or triacylglycerols.

1 molecule of glycerol + 3 molecules of fatty acid = 1 molecule of triglyceride + 3 molecules of water.

It's the fatty acids that determine whether a fat is sat, mono etc. The four different types of fatty acid all have a CH3 at one end and a COOH at the other. The difference is in the middle section.

Saturated fatty acids have a middle section consisting of all CH2's. Here's a diagram for Stearic acid (the predominant fatty acid in beef):-

__H H H H H H H H H H H H H H H H H OH-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-O-H__H H H H H H H H H H H H H H H H HMonounsaturated fatty acids have one C=C bond in the middle, which is usually (but not always) 9 from the left-hand end resulting in monounsaturates usually being referred to as omega-9's, as omega is the letter at the end of the Greek alphabet. Here's a diagram for Oleic acid (the predominant fatty acid in olive oil):-

__H H H H H H H H_____H H H H H H H OH-C-C-C-C-C-C-C-C-C=C-C-C-C-C-C-C-C-C-O-H__H H H H H H H H H H H H H H H H H

Omega-6 polyunsaturated fatty acids have two or more C=C bonds in the middle with the last one always being 6 from the left-hand end. Here's a diagram for Linoleic acid (the predominant fatty acid in sunflower oil):-

__H H H H H_____H_____H H H H H H H OH-C-C-C-C-C-C=C-C-C=C-C-C-C-C-C-C-C-C-O-H
__H H H H H H H H H H H H H H H H H

Omega-3 polyunsaturated fatty acids have three or more C=C bonds in the middle with the last one always being 3 from the left-hand end. Here's a diagram for Alpha-linolenic acid (the predominant fatty acid in flax-seed oil):-

__H H_____H_____H_____H H H H H H H OH-C-C-C=C-C-C=C-C-C=C-C-C-C-C-C-C-C-C-O-H__H H H H H H H H H H H H H H H H H

These diagrams are slightly misleading. Where there is a C=C bond, there are two H's on the "underside" only of the molecule. This asymmetry causes the H's to repel each other and bend the molecule into a V-shape at each C=C bond. C=C bonds with H's on the same side are known as "cis" bonds. The above molecule is really cis, cis, cis (c,c,c) Alpha-linolenic acid. The other type of C=C bond is known as "trans" and looks like the following diagram:-

__H H H___H H___H H___H H H H H H H OH-C-C-C=C-C-C=C-C-C=C-C-C-C-C-C-C-C-C-O-H
__H H___H H___H H___H H H H H H H H

This is a diagram of trans, trans, trans (t,t,t) Alpha-linolenic acid. As the H's are on opposite sides of the molecule, they do not repel each other and the molecule is straight as shown above. Note that saturated fatty acid molecules are naturally straight. Therein lies the problem with trans-fatty acids. They're straight, like saturated fatty acids but have unsaturated bonds which are prone to oxidation. See http://www.cyberlipid.org/perox/oxid0002.htm WARNING! Heavy-duty organic chemistry!

Our bodies take trans-fatty acids and incorporate them into cell membranes as if they were saturated fatty acids. This results in atherogenicity (artery-clogging), damage to the immune system and other health problems. Trans-fatty acids are found in partially-hydrogenated vegetable oils and so any processed foods or cooking/spreading fats which has the word "hydrogenated" high-up in the ingredients list should be avoided. These truly are bad fats. There are also naturally-occurring trans-fatty acids made by bacteria in the stomachs of ruminant animals, like Conjugated Linoleic Acid (CLA). This looks a bit like the diagram below:-

__H H H H H_____H___H H H H H H H H O
H-C-C-C-C-C-C=C-C=C-C-C-C-C-C-C-C-C-C-O-H
__H H H H H H H___H H H H H H H H H

This has one of the C=C bonds shifted to the left and also has one cis bond and one trans bond, so the molecule is always bent. CLA has possibly beneficial properties but medical studies show mixed results. It's certainly not artery-clogging, so don't let anyone put you off eating butter from grass-fed cows (e.g. New Zealand butter) by saying that it has trans-fats in it. CLA is a harmless trans-fat.

Anyway, back to diet. Saturated fat consumption should be about 10% of total calories. This is because, even though sat fats are not essential (our bodies can manufacture them), this guarantees adequate levels of sex hormones in the body. Total polyunsaturate consumption should be about 5% of total calories, with a ratio of omega-6 (O6) to omega-3 (O3) of between 1:2 and 4:1. As O3's are only found in greater quantities than O6's in flax-seeds (a.k.a. linseeds) and oily fish, and many people eat way too little or no oily fish (and who, other than body-builders and some vegetarians/vegans, eats flax-seeds?), the O6:O3 ratio in the West is about 20:1. This is due to the widespread consumption of meats, eggs & milk from grain-fed animals, grains, nuts and seeds. So, it’s not surprising that there are high rates of heart disease and other inflammatory diseases in the West, as O6's end up in series 1 & 2 prostaglandins and series 2 prostaglandins are pro-inflammatory. O3 fats end up in series 3 prostaglandins, which are anti-inflammatory.

So eat up yer oily fish if you're not vegetarian or vegan. Otherwise, eat up yer ground-up flax-seeds!

Monounsaturates can make up 15% to 35% of total calories, depending on activity levels. Remember from the histogram in the Blog post Everyone is Different, sedentary people on average burn twice as much energy from fats as from carbs. So, if energy from protein is 25% say, 25% of energy can come from carbs and 50% can come from fats i.e. a 2:1 ratio of fats:carbs. The cyclists at the left-hand end of the histogram in Chapter 1 would do best on 25% protein, 5% carbs, 70% fat when sedentary, whereas the cyclist at the right-hand end of the histogram would do best on 25% protein, 60% carbs, 15% fat when sedentary. When active, more carbs are needed by everyone.

Which fats contain which fatty acids? See http://homepage.ntlworld.com/nigel.kinbrum/comparison-of-fats.gif for a Comparison of Dietary Fats chart. Click http://www.apag.org/oleo/fatsoils.pdf for tables of Properties & Composition of Vegetable & Special Oils and Properties & Composition of Animal & Marine Fats & Oils.

For high-temperature cooking, saturates are the least likely to oxidise (when they're on fire, they're oxidising!), followed by monos, then omega-6's with omega-3's being the least stable. An oil doesn't have to be smoking to be oxidising. Alpha-linolenic acid oxidises at room temperature, which is why linseed oil is used to varnish cricket bats and soften putty. The best non-animal fat for high-temperature cooking is Coconut Oil, followed by Palm Oil and then Olive Oil. Extra-Virgin Olive Oil (EVOO) has a lower smoking temperature than refined Olive Oil (due to higher levels of free fatty acids), but has higher levels of polyphenol antioxidants, which makes it pretty heart-healthy.

Oils high in polyunsaturates shouldn't be heated above 100°C, as polyunsaturates can change from the cis configuration to the trans configuration at temperatures as low as 102°C. See http://www.harricksci.com/sites/default/files/pdf/application_notes/FatIR_App-Notes_ATR_Oil-Analysis.pdf