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Posts Tagged ‘calories’

The current theory that dominates medicine, science, media and most peoples opinions today is that overconsumption of calories causes obesity. If you overeat you get fat. Simple physics right? I propose that instead of this old premise, overeating is a consequence of our body putting on fat. This is a subtle but rather major difference. If some other factor is the cause of obesity then it will make no difference how much energy we consume because this is the resulting behaviour, not the cause. I am going to try and show evidence that obesity is caused by a defect in fat metabolism and homeostasis. The human body has many biological controls on how fat is stored and any change in these controls can have large consequences that results in obesity. 

 If overeating was the cause of obesity then by reducing the calories you eat you would lose weight. This of course is obvious to everyone. But what if it is wrong? It is well known, much to the medical communities frustration, that only 1% of diets work. Clearly, reducing calories has not resulted in a reduction in obesity. In fact, in many situations obese people have been shown to consume less or as much calories as their lean counterparts but still remain obese. A reduction in calories does not necessarily mean a reduction in weight. Only on extremely restrictive diets do obese people lose weight but they are found to lose muscle and fat from their organs and often still maintain a very high level of fat in their adipose tissue – they are simply emaciated fat people. 

However, some of the best examples to prove this point is through animal studies, which can directly test whether obesity is caused by eating too many calories. We simply ask ‘when animals become obese do they do this by eating more calories’? The examples I will give involve influences from genetics, neurobiology, hormones and natural circadian ryhthm’s.  

The first example I give looks at animal hibernation, which decouples food intake from weight gain. Hibernating squirrels will double their body weight during late summer in preparation for the hibernation in winter. This is remarkably controlled and unaffected by food intake. Squirrels in the laboratory will gain this weight even if calories are severely restricted. In addition, if the fat stores are surgically removed they will still gain that fat back very quickly despite limits on calories. This seasonal fat deposition is strongly genetically programmed and is robust to changes in food supplies. 

Investigators who have looked at weight regulation and reproduction have also shown this. Female rats who have had their ovaries surgically removed exhibit a reduction in the amount of the female sex hormone estrogen. Without estrogen the rats develop out of control appetites, severely reduce their physical activity, and quickly grow obese. Rats put on weight even if their diets are restricted to what they were eating before the surgery. When estrogen is infused back into the rats they lose the weight and adopt the normal eating and exercise behaviours exhibited prior to surgery.  Thus, calorie intake and physical activity were directly influenced by a change in hormone levels.  

Mice who have had lesions applied to their hypothalamus (a region of the brain that regulates fat metabolism) become severely obese and gain six times as much weight per calorie of food compared with normal mice. These mice became so lethargic that they barely move and develop voracious appetites. Again a change in the biological controls of fat storage results in changes in eating and physical behaviour – not the other way round.  

Genetic studies on obese strains of rats show that individuals that are placed on a restricted diet from birth onward, grow fatter by adulthood than their littermates who were allowed free reign over what they ate. Therefore, calories did not effect the obesity of these rats over their lifetime. Quite the reverse a reduction in calorie consumption seemed to be associated with increased obesity.  In addition, those rats on a restricted diet had 50% less muscle mass than normal rats and 30% less muscle mass than their counterparts who could eat what they wanted. Emaciated fat mice. 

It is clear from these animal studies that the intake of calories has no influence on weight gain. In some cases the animals would severely reduce their physical activity becoming very lethargic. However, it would be difficult to propose that a reduction in physical activity was the CAUSE for these changes but rather an associated behaviour. These studies certainly suggest that the cause of obesity is some error in fat metabolism or homeostasis that leads to increases in fat deposition and changes in behaviour (overeating, lethargy). 

In this final and human example I hope to put an end to the hypothesis that overeating is the cause of obesity. There is a rare condition known as lipodystrophy. In one case in 1913, a ten year old girl first loss fat from her face, then, over the next three years, this emaciation gradually extended down her trunk and arms. Obesity of the lower body began at fifteen and by the time she was 24 she had all the body fat localised in her lower waist. You can see the example below. 

This is clearly not a case of overeating. The most obvious explanation is fat was placed due to some genetic or hormonal condition. In fact, this is seen in the differences between the sexes. Males tend to store fat around the waist while females at the hips and this is large genetically and hormonally controlled. Although these are obvious examples they do beg the question – is fat deposition controlled by our biology and physiology or is it controlled by our behaviour. If it is not controlled by our behaviour then it is difficult to argue that obese humans are that way because they have no willpower, eat too much and do not exercise. Obesity is likely to be a defect in fat metabolism which results in overeating and lethargy. Asking obese people to change their eating patterns or to exercise more is equivalent to telling a seven foot man that they need to stop eating and exercise less in order to become shorter. 

Soon, I will talk about how I think obesity is controlled by our biology, how we get fat DESPITE calorie consumption and what we can do about it.

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I cannot believe that I only ate 1600 calories today and I am NOT hungry. I simply am amazed at this. I literally do not feel hungry at all. I am starting to get used to the meals and that horrible nausea has gone. But most of all I am simply NOT hungry. Still feeling a little weird about not eating the veges but I did have a whole brocolli head today and it didn’t blow me over my carb budget. So I think I am getting to know how to do this. 

On a more negative note I didn’t do so well on the exercise today. My heartbeat was rising very quickly and I did not burn off as much calories as I normally do by keeping my HR between 145-155 heartbeats per minute. I will monitor this. 

Today I ate:

Breakfast:

50g Edam Cheese

Lunch:

Curry Chicken: Full cream yoghurt, Garam Masala, Turmeric, Cloves, Garlic, Chilli, Ginger, Brocolli, Skinless Chicken, Mint, Canola Oil

Dinner (ATKINS STYLE)

Pork, Eggs & Butter

Exercise

20 Mins Brisk Walking on Treadmill – 143 calories

Total Calories – 1623

Carbohydrates – 20g (13.6g sugar)

Fat – 90g (33.1g Saturated Fat)

Protein – 206.7g

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What a great day. I have simply not felt hungry today. When I finally did get hungry at about 8pm I just had an egg and tomato salad and was no longer hungry again. I cant quite believe it! In fact I have only eaten 1500 calories today and this is much lower than what I can eat but I just dont feel hungry. Over the last few days I have stopped eating potatoes and the dried fruits and have tried to minimise carbohydrates by having only a few fruits and a handful of nuts. I am literally not feeling hungry and this may be why. OR it could just be that I am not having a hungry day but that has never happened on a diet before so I feel a bit insecure about the whole situation. Not been hungry on a diet kind of scares me to be honest. Its almost as if I would rather brace myself for the hunger rather than start to feel like I wont be hungry and then have hunger set in. Anyway.

As for the exercise I am doing so well. I am almost running now. Well I am walking so fast I dont think that I could walk any faster. My heart is relatively cool and not beating too fast so its obviously adapting well to the exercise regime but my poor legs cant seem to catch up. I might try stretching them pre work outs and not just post work outs and see if that helps. But it amazes me than within a week I am at this level of fitness. Today was good. 

Also Im starting to ponder the goodness or badness of dairy. As far as I can see it seems to be carbs that are the main cause of our modern diseases of civilization. So dairy? It certainly would add some diversity to my cooking. Would be interested in peoples feedback on this but for now I will keep leaving it out. But expect a post soon as I want to look into the research to see the good and the bad. 

Breakfast

Apple, Orange and a handful of cashew nuts

Lunch

Tuna salad: Lettuce, Tuna, Long eggplants (skinny version), Mint, Olive Oil, Spring Onions, Tomato


Dinner

Steak and Guacamole with salsa: Sirloin Steak (grass fed of course), Avocado, Olive Oil, Lime, Tomato, Cucumber, Onion, Capsicum, Coriander, 

Supper

Egg and Tomato Salad: 3 Eggs, Tomato, Onion

Snacks

Apple, Carrot

Total Calories – 1610 (oops not the 1500 I said but still well under my daily allowance)

Exercise – 20 mins brisk walking (161 calories)

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I decided three days ago that I had had enough of being and feeling fat. I had a hiatus of a few years of attempting to lose weight. I had enough of trying and then failing to do it. But then I read the paleo diet by Dr Loren Cordain. The premise of the book is to eat what we as humans evolved to eat. He uses his own and others research to determine what humans ate during the paleolithic times and also what hunter gatherers eat today. Then he developed guidelines on how to best simulate their diet. Why would you want to do this? Well humans have had around 100000 generations since our existence and of which 500 were after the agricultural revolution. Our bodies simply have not evolved to eat these new foods such as potatoes, grains, junk food, dairy etc. Evidence shows that our ancestors and hunter gatherers just did not get sick with the modern diseases of civilization but rather died from infectious diseases and trauma ie being bitten by a tiger or something. As a biologist myself who studies evolution I can personally back this philosophy. So I chose to once again try and attempt to lose weight following these principles. This is my journey…..

So I have been following this for the last few days. I have made sure I am eating under 1800 calories a day. But I am starting to wonder if this is too low as I have dropped 2kg (4.4 pounds) in the last two days. I know however that this is probably water. I will carry on for a week and see what happens but if the weight keeps coming off too fast I may eat more. My body has major issues with this diet. I have been very hungry at night and experiencing very strong headaches. Headaches I have not felt before. I believe this is sugar withdrawal. I have seen on TV whenever people go on such diets (ie no sugars or grains) they experience the same thing. Hopefully this will simmer down over the next few days. 

The headaches seem to be subsiding but now my problems seem to be in my intestinal area. Yes in one word Im constipated. I have been eating many many vegetables and lean meats. For example yesterday I had.

Breakfast: Banana and Cashew Nuts 

Lunch: Salad, beetroot, onion, monkfish, lemon juice, capers, tomato and olive oil

Dinner: Canola oil, 6 tomatoes, onion, 250g frozen spinach, 300g Lean skinless chicken, Spices

Snack: Dried rockmelon, Potatoe with olive oil (yes this is not allowed but my head was exploding and felt like this might relieve it. Im easing myself into paleo slowly). 

 So as you can see I am getting fibre. Additionally, my stomach keeps rumbling and feels very acidic and out of sorts. I guess it takes a while for all the bacteria in your gut to sort themselves out so that the ones that can break down vegetables become more dominant. Also my body may be releasing too many acids (perhaps) because of years of feeding it fatty and starchy foods. Anyway I will keep an eye on it over the next few days.

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