No food group should be ‘demonised’. To me, a real balanced diet would have the best of all worlds, enjoying fatty food and not having to shun all carbs or constantly count calories. The worst of both worlds is a diet high in animal fat and refined ‘fast releasing’ carbs and sugar – the hallmark of today’s average diet. Studies show that this combination creates the equivalent of junk food addiction and rapid weight gain.
Why Dual Fuel Has Become a Problem
We are not designed to eat the same thing every day. The fact that our bodies can run on either glucose or ketones gave us a huge evolutionary advantage because we could wolf down abundant carbs in the summer and survive through the winter on our reserves of fat. However, many people’s diets are very different now, and this has contributed to the rise of many of the chronic diseases of the twenty-first century. Year round, people gravitate towards junk food that provides half the calories from sugar and half from fat. This triggers insatiable hunger - a malevolent ‘sweet spot’ that is virtually known in nature:
• Grains are mostly carbs and a little protein.
• Beans are mostly protein and a little carbs.
• Nuts and seeds are mostly fat and protein.
• Meat, fish and eggs are fat and protein.
• Fruit is almost all carbs.
• Hard cheese is fat and protein.
• Milk is fat (49 per cent), protein (21 per cent) and carbs (30 per cent).
The only food group that is both fat and carbs is milk - designed to be addictive and prmote rapid weight gain. Variation in your diet, not moderation, is the key to health. Here I explain why.
Approaches to Diet: Calories in/calories out model versus Carbohydrate-Insulin model
The big problem with conventional approaches to diet is the ill-founded belief that calories in (from diet) minus calories out (from exercise and the energy needed to run your body systems, i.e. your metabolism) is the only thing that determines your weight. While it is true that you would grow if you did nothing but eat, and you would shrink if you did nothing but exercise, this ignores all the metabolic complexity, and flexibility, that is built into our design. In part, that flexibility is controlled by the hormone insulin.
This is why Harvard Medical School’s Professor of Nutrition, David Ludwig, puts insulin at the heart of his ‘Carbohydrate–Insulin Model of Obesity’, which really should replace the outdated ‘calories in, calories out’ approach. Put simply, the conventional recommendation to eat low calorie by cutting fat because it has the most calories per gram (1g fat = 9 calories while 1g protein or carbs = 4 calories) means you end up eating lots of carbs, which means more insulin production, which means more sugar is converted into fat and stored in the body. Furthermore, as the insulin drives down your blood sugar, you start to feel hungry.
If you eat the opposite – a high fat, low carb diet – your insulin level falls, which drives fat out of storage to meet the body’s energy requirements. Furthermore, the fat satisfies your hunger. Alternatively, if you eat low, slow carbs – that is, small amounts of slow-releasing carbohydrates – your body doesn’t need to produce much insulin, so no fat is stored and you don’t suffer the blood sugar dips that drive hunger. Going Hybrid incorporates both of these options.
Insulin isn’t ‘bad’ per se. It’s an essential growth hormone. However, too much of it, and specifically developing the condition known as ‘insulin resistance’, lies at the heart of almost all of today’s endemic non-infectious diseases. Insulin resistance is a bit like an addiction: your body keeps needing more and more to have the same effect. This leads to very high blood levels (hyper-insulemia), which has all sorts of damaging effects.
MEET mTOR – the Body’s ‘Fat’ Controller – not to be demonised
The Calories in/calories out model is not the only model that has been wrong. mTOR was blamed for the obesity epidemic, diabetes and much more besides. The theory went that, while we need it to grow during childhood, by the time we arrive in middle age the growth it promotes is more likely to be cancerous, a bulging waistline or a build-up of plaque in the brain. As a result, the notion took hold that the secret to living a longer, healthier life is to turn off mTOR permanently. In short, it became public enemy number one – the new saturated fat or cholesterol – and pharma companies rushed to develop drugs that would block it, then marketed them as anti-ageing treatments.
Your body is in growth mode when mTOR is switched on, but that doesn’t mean that you just pile on ever more pounds of fat. For instance, it is activated by and works with insulin and IGF-1 to build up muscle. This is crucial, because maintaining muscle tone is vital for health, especially as we get older. mTOR activation is also essential for the cell division that we need to replace exhausted blood cells and worn-out gut lining. It is thanks to mTOR that we are able to make 2,000 new white blood cells every second and replace our gut lining, which is the size of a tennis court, every four days.
mTOR is switched off at the start of exercise in order to maximise the delivery of fuel to the muscles. However, it is reactivated as soon as you stop in order that your body can resume its routine repair tasks and start to lay down more muscle, if necessary. This is why you should always eat protein after exercise if you want to build or maintain muscle. (By contrast, coffee suppresses mTOR, so make sure you drink it before exercising, rather than afterwards.) Different types of exercise affect mTOR in different ways.
Finally, you will find it very difficult to fight off an infection if you permanently deactivate mTOR. This is because it plays a crucial role in the immune system’s rapid production of T cells during glycolysis. The downside is that cancers’ rate of growth also increases during glycolysis.
However, this is not such a great idea, as the first drug to do just that, the one that gave mTOR its name – rapamycin – is associated with insulin resistance and sky-high levels of blood glucose when it is used in the treatment of cancer. Indeed, anywhere between 13 and 50 per cent of patients who are treated with rapamycin develop diabetes. Moreover, the vilification of mTOR was based on a misunderstanding of how it works.
mTOR AND GOING HYBRID
Mammalian target of rapamycin – or mTOR for short. (Rapamycin is an immuno-suppressant, so the name is a reference to the enzyme it inhibits.) mTor is a sort of general contractor that is in charge of the major repair projects that your body is constantly undergoing.
As Professor David Sabatini, biologist at the Massachusetts Institute of Technology, who studies the basic mechanisms that regulate growth, says ‘[mTOR] has a finger in every process in a cell’. For instance, as well as carefully monitoring amino acids in the body and proteins in the diet, it responds to and organises signals from insulin.
The details are very complicated, but the bottom line is simple. Ultimately, mTOR is a prudent chancellor that runs your internal economy. Its main job is to promote growth, so it has to monitor the body’s fuel supplies closely.
If the body’s fuel starts to run low (as it would on a ketogenic diet or intermittent fasting), either mTOR switches itself off or it is switched off by ‘autophagy’, which then assumes responsibility for repair and restoration while the body waits for fresh fuel supplies. You will reactivate mTOR when you shift back to slow carbs/glucose fuel supply.
The ketogenic diet became popular because it promised a healthy alternative to overdosing on carbohydrates and achieved rapid, impressive results in terms of both weight loss and reversing diabetes.
These are the natural consequences of a high fat diet because the body releases much lower quantities of hormones such as insulin and IGF-1 (insulin-like growth factor) – both of which are linked to weight gain – and, crucially, turns off mTOR altogether.
Unfortunately, this highly sophisticated, efficient system, which has been honed by millions of years of evolution, has been caught out by the massive oversupply of carbohydrates in the modern world, and the associated exponential increase in blood glucose levels.
I’ll be explaining more about ‘autophagy’ in another Report.
Take a Break from Carbs - PRACTICE Nutritional Yoga
By switching between a high fat phase – which turns off mTOR and growth, and turns on autophagy – and a slow carb phase – which promotes healthy growth and repair – you get the best of both worlds and allow insulin, IGF-1 and mTOR to orchestrate all of the growth processes you need to thrive.
One of the interesting effects of taking a break from slow carbs and running on ketones for a while is that you will have even better blood sugar control when you return to the low GL diet.
This is because your metabolism gains flexibility in the keto- genic phase and you become ‘carb adapted’ – able to use carbs more intelligently. Moreover, after some time on the low GL diet, you will be ‘fat adapted’ when you choose to switch back to the ketogenic diet. This means that you will enter ketosis more rapidly, and the symptoms of ‘keto flu’ (see page 46) will be milder.
This increased metabolic flexibility is due in part to reversing insulin resistance and becoming more sensitive to the hormone’s effects, but it is also linked to the fact that mTOR is being turned on and off appropriately. This means that your body learns how to keep blood sugar low, and weight and energy levels balanced.
Also, by experimenting with the two principal fuels – glucose and ketones – and monitoring their effects, you will become much more aware of the impact of specific foods and drinks, which will help you to make better choices. Think of it as a form of nutritional yoga in which you use all of your energy-generating options to keep yourself flexible and well adapted.
THE 5 DAY DIET
One way to get into ketosis is by fasting. The trouble is only the brave are willing to do it. There are many variations of intermittent fasting. All these have their merits and reasonable evidence, or at least logic, to support them. All will have the potential to briefly trigger autophagy and nudge your metabolism away from glucose, made from carbs, towards ketones, made from fat, including burning your own body fat.
Yet I do not believe that they are nearly as effective as five consecutive days of fewer calories, with not too much protein, and consuming food, supplements and drinks that is specifically designed to trigger autophagy - which is the key to the ability of fasting to transform your health, rejuvenate your cells and switch you out of a disease process.
In 2019 I wrote the book The Hybrid Diet, with award-winning medical journalist Jerome Burne explaining the theory and some practical information so you could create your own diet.
I followed it up in 2020 with the more prescriptive 5 Day Diet. We've now run three groups of people following this diet, measuring weight and body fat. In each group the average weight loss was close to 3kg each, roughly 7lbs, almost all of which was fat. In the last 5 Day Diet retreat experiment the greatest loser lost 11lbs. This kind of healthy weight loss is unheard of. No diet - 5:2, keto, low carb, 18:6, weekly fasting even conventional FMD has achieved this, also with no hunger.
If you think you’d like to try a diet based on this new science, then take a look at my 5 Day Diet book which summarises the science while giving you daily meal plans, recipes, a supplement programme and exercises. The diet has been devised to help you kickstart ketosis, lose weight, gain energy and transform your health in just five days. The book is available from HOLFORDirect - FREE with the supplement combo needed to get cracking with the diet - or the book is available on its own.
5 -DAY DIET TESTIMONIALS
If you want to read what others who have done the diet have to say about it you can read their testimonials here.
5 DAY DIET RETREATS
Details of the retreat are on my retreat events page.
Details of the room options are found at Holford Natural Holidays.