Understanding is key to anything in life. If you don’t fully understand the principles and concepts of what you are doing you can never be fully successful at it. This is especially true with LIHF. You MUST have at least a basic understanding of the physiology behind LIHF in order to a) apply it fully and effectively in your own life and b) be able to explain clearly to others when people ask “how/why does it work”? Understanding brings with it confidence and ultimately success!
After understanding comes “acceptance”. You need to accept the new found information regardless of any previous misconceptions/prejudices. This usually requires “proof” or “evidence”. Acceptance is usually the most difficult part for people, since this might run contrary to any previously held convictions, cultural and/or religious norms. This is very much the case with LIHF. The current “low fat” meme has been so strong for the last 40 yrs or so that this is very hard to shift out of both the individual and society as a whole. Yet the evidence is all around us that “low fat” is not working. Obesity rates are sky-rocketing out of control globally and there is no sign of the upward trend changing in the near future.
I will try to make this as simple as possible so that you can “understand”, “accept” and finally “implement” LIHF with confidence in your own life. So let’s begin..
The food we eat can be broken down into 3 main macronutrients, namely: PROTEINS, FATS & CARBOHYDRATES. The role of each with regards to our physiology is as follows:
- PROTEINS: the building blocks of life that go into making our hair, teeth, skin, bones, etc., and are considered essential i.e. the body can not synthesize them by itself and so they must be provided through diet. Since they are considered essential, without them you will die.
- FATS: Fatty acids serve multiple functions in the human body and are also considered essential. Also, on a CARBOHYDRATE restricted diet, FATS will also be used as a source of energy through a process known as ketosis. Note: In order to maintain an “energy balance” for carbohydrate restricted diets it is important to increase fat intake accordingly.
- CARBOHYDRATES: Carbohydrates are sugar molecules and chains of sugar molecules. They act as a source of energy since they are readily converted by the body into glucose, one of the “fuels” that keeps us going. NOTE: No individual carbohydrate is an essential nutrient for humans! This is a vital concept in understanding LIHF.
To summarize: if you leave out certain FATS and PROTEINS from your diet you will eventually die but if you drop CARBOHYDRATES completely from your diet, nothing will happen, apart from the fact you will just start burning stored FAT, gently slip into ketosis and start losing weight accordingly.
Energy, Blood Glucose, Ketones & Insulin
These are all related in one way or another and it’s important to understand how and why.
Glucose is our body’s fuel. It provides us with the energy to move our muscles and get us out of bed in the mornings. Once ingested, most carbohydrates are converted into glucose, the exception to this being fructose which follows an entirely different metabolic pathway. This is discussed separately below. Depending on the type of carbohydrates consumed, upon entering the digestive system there is an almost immediate spike in blood glucose which is accompanied by a similar spike in insulin. The “excess glucose” due to the spike is immediately converted into fat and stored, thereby resulting in weight gain. This process is known as lipogenesis and, just like frying an egg, is non-reversible i.e. once the egg is fried it can not be “un-fried”.
Insulin, produced by the pancreas is the hormone that drives blood glucose into our body tissues for energy. It also regulates excess blood glucose levels by converting glucose into fat (lipogenesis) and storing it. This is a VITAL concept in understanding how and why we put on weight on high-carb diets. The inability to produce insulin as an inherent pancreatic disorder is known as Type 1 Diabetes (T1D). People with an otherwise normal pancreas on a high carbohydrate intake run the risk of becoming insulin resistant i.e. insulin is produced but is not effective anymore and leads to Type 2 Diabetes (T2D). In either case, unless carbohydrate intake is restricted, subjects will need to take on further insulin in the form of daily injections. There is no known cure for T1D but in the vast majority of cases T2D is entirely reversible through appropriate lifestyle changes e.g. an LIHF diet.
Ketones are the body’s response to carbohydrate restriction. On a carbohydrate restricted diet, the liver begins to produce ketones from fat, either stored around the body or ingested as food. Fat therefore becomes the primary source of fuel. Ketones are an “alternative” source of fuel for the body but by no means exceptional. In fact, for the brain, ketones are the preferred source of fuel. Hence, by restricting carbohydrate intake, the body moves into a state of ketosis i.e. it becomes ketogenic.
Fructose deserves a mention all of its own. Why? Because the human body can not convert it into glucose and insulin has no effect either. Instead, most of it is converted into fat by the liver. Common sources of fructose include all natural fruits, their juices and High Fructose Corn Syrup, a common food additive. High fructose intake places a large stress on the liver, an otherwise very sensitive and important organ. This not only leads to non-alcoholic fatty liver disease but, if left untreated, eventually also cirrhosis, a condition which may lead to the requirement for a transplant. In short, with the exception of a few in-season berries every so often I avoid ALL other sources of fructose like the plague!
This is an important part of LIHF as well as healthy living in general and it is therefore equally important that you understand both its causes and effects. Inflammation is the human body’s response to invasion or attack from foreign bodies, the so-called “autoimmune response”, mainly in the form of the production of white blood cells. Causes of inflammation are many but include disease, infection, ingested food, etc., etc. It is important to note that inflammation is NOT necessarily synonymous with infection i.e. it is possible to be inflamed without being infected. It is now an indisputable fact that there are strong links between long-term inflammation, atherosclerosis, T2D, obesity, cancer, strokes and a whole host of other disorders too numerous to mention. Hence, it is important to avoid all sources of longer term inflammation in order to maintain a healthy lifestyle.
Measuring Inflammation & link to Carbohydrates
One of the most common and direct ways to measure inflammation is through C-reactive protein (CRP) taken as a blood sample. CRP is a protein produced by the liver in response to inflammation. High levels of CRP are associated with elevated insulin levels in the dietary context and, by extrapolation, a reduction in ketone levels. Since carbohydrates are the primary cause of elevated insulin, reducing carbohydrate intake also reduces inflammation. Hence, serum ketones may also be considered an indirect albeit more rudimentary marker for inflammation. To put it simply, if you are putting on weight as adipose (fat) tissue rather than muscle then you are inflamed, and if you are inflamed you are at increased risk of falling victim to the diseases mentioned above.
Measuring CRP requires a laboratory but measuring ketones can be done at home using either urine testing sticks or a more accurate blood glucose/ketone testing kit. Hence, if you are losing weight and you have elevated ketone levels, you can be pretty sure that you also have reduced levels of inflammation and the risk of you acquiring the above diseases is greatly reduced.
Dietary Inflammation & link to Dairy Products
As discussed above, in the dietary context, carbohydrates are considered to be the primary cause of inflammation but there are many others. In my case, I found that dairy was a major source of inflammation, see My Progress with LIHF. When I started LIHF, it wasn’t until I dropped ALL dairy that I achieved the majority of my weight loss, some 10kg in only 6-8 weeks! My own personal experimentation as well as further research have led me to the conclusion that dairy products are NOT suitable for the large majority of humans, mainly due to the animal proteins and bovine insulin they contain which are highly glucogenic and are not removed during pasteurization. Hence, I have removed ALL dairy from my diet and I feel much better for it!
Further, it is my opinion that the LIHF community is making a big mistake when it encourages the liberal consumption of dairy products, mainly due to their higher fat and lower carb content, only to then completely ignore their highly glucogenic effects altogether! Dairy is the reason I almost gave up on LIHF. I am sure other potential LIHF practitioners in the past have also managed to successfully reduce their carb intake whilst maintaining or even increasing their dairy intake. No doubt they lost some weight but not enough and “plateaued” as I did for over three months with minimal/no weight loss at all. Utterly demoralized they probably gave up altogether blaming “poor science” as the reason why LIHF did not work for them when in fact there is absolutely nothing wrong with the science at all, just a lack of awareness about the inflammatory effects of dairy. As far as I’m concerned, dairy is the enemy within when it comes to LIHF and should be avoided in all but very small amounts.
I have found that the longer and stricter my LIHF diet has been, the more sensitive I have become to any food allergens. For example, feta cheese and rapeseed oil cause me to sneeze and my eyes to water, especially during the hay fever season. For all my life I have suffered from hay fever to varying degrees. Once I went LIHF and in particular when I dropped all dairy, I have had no symptoms at all. I now also avoid all spicy food on the premise that if something causes a severe burning reaction in your mouth, it is very likely to be inflammatory, albeit short term.
- Carbohydrates cause increases in blood sugar and hence also insulin which in turn causes weight gain.
- Elevated insulin levels are associated with inflammation, which are attributable to potentially fatal diseases.
- Carbohydrate restriction leads to ketogenesis and hence “fat burning” or weight loss.
- Fats and proteins are essential nutrients, carbohydrates are not.
- The body uses both blood glucose and ketones as energy, with the brain in particular preferring ketones as its primary energy source.