I measured glucose and ketone levels thirty minutes after starting each meal, then glucose level two hours after finishing each meal. This meant I could then calculate my Glucose Ketone Index (GKI).
Figure 1 - G, K and GKI scores over the course of three high fat days
This shows the effect of starting the high fat phase with a fifteen-hour fast between the previous night’s dinner and Day 1’s breakfast. The vegetable chilli in the evening of Day 1 pushed up my G score, but it soon fell back down to base level. Day 2 started very well with a Hybrid Latté, which I’ve found consistently lowers G and raises K, and the rest of the day was good, too. The G score spike on Day 3 was due to exercising. Glucose is liberated from the body’s reserves of glycogen when the muscles need more than usual, and thereafter it can be a couple of hours before blood sugar settles down again. By the end of Day 3, my K score was between 1.5 and 2mmol/l (mild ketosis), while my G score was steady at around 4mmol/l. My GKI was right in the middle of the ideal range at about 3.
This brief experiment revealed that the quickest way to enter ketosis is to fast, either completely, for a day or two, or for fourteen to sixteen hours (early dinner, late breakfast), then drink a Hybrid Latté for your Day 1 breakfast, then avoid all carbs (except those that are in green vegetables) throughout the rest of the day and into Day 2.
SLOW CARB PHASE
Next, I switched to three days of slow carbs.
Figure 2: G, K and GKI scores over the course of three slow carb days
I started Day 1 with a Get Up & Go shake with some berries, then had an apple and some nuts as a mid-morning snack, followed by a big bowl of Chestnut and Butter Bean Soup for lunch, then a late afternoon snack. As you can see from the figure aboce, my G score increased to more than 7mmol/l after each meal or snack, but soon fell back down to about 6. The evening meal had quite a low glycemic load (8 GL), so my G score peaked at just 6.5 before falling to less than 5 by late evening, where it presumably remained throughout the night. (I did not conduct any measurements during the night).
I started Day 2 with a quite low G score of 4.8mmol/l. Coffee brought it up to 5.7, then I had chia and oat porridge with berries before a half-hour cycle ride through London. This combination of food and exercise generated a peak of 9, but my G score soon fell back to 5 and stayed there even after a mid-morning snack. I went off piste at lunchtime by eating out. The delicious meal consisted of a mushroom starter followed by tempura haddock with cauliflower cheese and peas, plus a glass of Chardonnay. Nevertheless, by 3 p.m., my G score was just 6 and falling. I had a slice of Almond and Apple Cake when I got home, which pushed it back up to 6. After dinner, it peaked at 7, but it was back below 5 by 11 p.m.
On Day 3 I went for a half-hour run before breakfast, which helped to push my G score up to 6.7mmol/l, but by midday it was back down to 5. It peaked at just 5.9 after lunch, then again after a slice of Carrot and Walnut Cake at 4 p.m. But thereafter it steadily declined to 4.7 before dinner at 8 p.m., which I enjoyed with a glass of white wine. (You can allow yourself the occasional drink or dessert during the slow carb phase.) By 10 p.m., I was back below 5.
As you can see from the figure, I was nowhere near ketosis throughout this three-day slow carb phase, whereas my blood sugar level undulated like a range of small hills. This sort of response to food indicates that the body is not secreting large amounts of insulin production, little glycosylation is occurring in the blood, and no sugar is being converted to fat for storage. My blood sugar remained very stable throughout, although the average reading was rather lower on Day 3 than Day 1 because by then I had become ‘carb adapted’. If a diabetic were to achieve these results over a somewhat longer period of time, they could abandon their medication as they would no longer be classified as having diabetes.
So, what did following the Hybrid Diet for four weeks do for me? Well, at the start of the ‘warm-up’ period, I weighed 12 stones (76kg). By the end of the second slow carb phase, I weighed 10 stones 6lb (66kg) – roughly the weight I was in my twenties. And this was achieved without any change to my exercise routine.
Remember, you will lose 4 or 5lb (2kg) of fluid from your body at the start of the high fat phase, then put it back on as soon as you begin the slow carb phase, so factor this in if you weigh yourself on those days. However, you will lose roughly equal amounts of real weight (i.e. fat) in each of the two phases of the Hybrid Diet. If you follow our guidelines and don’t have too many lapses, you should expect to lose about 4lb (2kg) each week – that is, more than a stone in a month. Most of this is fat.
Here's what other dieters have said about the diet:
“I have lost 12lbs (5.5kg) and 7.7lbs of body fat in three weeks on the Hybrid Diet. I followed slow carbs/low GL for two weeks and high fat/keto for one week. I am delighted with the result and feel more energised. This isn’t a diet, it is a lifestyle way of healthy eating and living. I feel in control of my body and the plan makes it very easy.”
Paula T, London
“I lost 12 lbs (5.4kg) in weight, 5 inches from my waist and 4 inches from my hips. I followed slow carbs/low GL for the first two weeks and felt switched on as soon as I woke up. No lethargy. Full of energy and vitality throughout which was unlike me. I switched to the high fat/ketogenic phase in week 3. Initially felt cranky, irritable and tired. Interestingly, I was not at all hungry during the fasting periods. At the end of week 3, I feel wonderful.”
Aine T, Dublin
“I lost 8lbs (3.5kg) and 7.5lbs in fat mass. I followed low GL for the first two weeks and the high fat phase in week 3. On ketosis I felt tired and had some headaches which lasted for the first 3 days. Overall my PMS symptoms significantly improved, and bowel movements became more regular. I feel more energetic and am sleeping more so that in turn avoids my evening snacking habit. I feel really pleased with my progress and feel confident that I can continue.”
Eloise H, London
“I was getting really fed up with my weight and feeling fatigued. I decided I needed to make changes before it got out of hand. I have been following The Hybrid Diet and done it along with my usual workout routine which involves weights at the gym. I've lost 16lbs in three weeks! The diet is easy to follow because Patrick Holford's cookbooks provide lots of recipes … meal prepping is easy and I batch cook. I was really unsure about starting the 'high fat' phase as I hadn’t done anything like this before. I needn’t have worried. I haven't felt hungry and my energy levels have soared!
Rebecca C, Pembury
'I had put on alot of weight on holiday and coupled with reaching my late forties realised I had developed middle aged spread! I was also interested in the celluar clean up the diet promises, as I want to stay as healthy as possible so I can be around for my kids. I felt very unsure about whether the diet would fit in with family meals and the 'high fat' phase seemed quite intimidating on paper. But I have been surprised by how normal I feel running on ketones (no side effects) and how easy it is to adapt the diet to family life. I have started each of the high fat phase days with a Hybrid Latte which really works. I haven't completed the first four weeks yet, but at 3 weeks I have lost 9lb and the fat around the middle has visibly diminished. So far so good!'
Clare S, East Sussex
About the Book
The Hybrid Diet is available from HOLFORDirect and they have it on Special Offer for £11.00 (RRP: £16.99) from 21 to 31 May 2019..
MORE ON THE DIET
More info and a short film can be found at www.hybriddiet.co.uk