I’m now 3 months into my “low carb, high fat” diet, or LCHF as it’s known. The radical change in my diet (particularly as I was also veggie and have now become carnivorous again) has provoked curiosity and humour amongst friends and colleagues and straight criticism from those who know me less well. Many people have been genuinely intrigued by the science behind it and although most people would love to eat more fat in their diet, most are still a) anchored to carbohydrates (bread, cake, pasta, sweet potatoes…. We all have our vice!) and b) find it hard to get past the “fat is bad for you” message that we’ve had preached at us over the last few decades.
So, how am I finding it? In short, it’s generally been ok. I decided to go straight for keto-adaptation through nutritional ketosis and dropped my carbs right down. This means 20-30g of carbs a day which has meant taking anything that is pure carbohydrate or contains sugar out of my diet. Breakfast – no porridge, cereal, toast, hash browns, waffles. Careful with milk intake as milk is high in carbs relatively speaking (10g carbs in a cappuccino ☹) No bread (of any description), no cakes, biscuits, pasta, sweets, rice, dates, bananas or other fruits (a few berries are allowed) and being very careful with vegetables grown below the ground like carrots and swede.
The restriction has been reasonably easy – I stopped eating cake and biscuits at work a few years ago as I didn’t trust myself to resist temptation. I make low carb brownies so we do have treats at home and we are allowed cream and dark chocolate and full fat yoghurt as well as cheese so desserts are still possible. I love eggs and cheese so these are going down well and there are lots of tasty breakfast options. Coffee has cream added and there’s liberal dressing of salads with olive oil and lots of fat when we’re cooking meat.
Yes, it’s weird! There are some days when I crave some of the dishes I used to eat – sweet potato and chickpea bake or bean quesadillas. I’m enjoying eating meat again but still love my salmon with herb crust or prawn curry. Sometimes, you just simply don’t want something fatty and I do miss having fruit. Is it healthy not having it – yes, because we eat lots of vegetables. I do still eat a balanced diet, just not with too many carbs because the body can make what it needs.
The first 3 weeks I did hit a low point and felt terrible. This happens whilst your body is making the switch from burning glycogen to using ketones (by-products of fat metabolism). It takes a good few days for that shift to happen and whilst it does, you feel drained and unable to exercise. I tried to push through but frankly I just wanted to curl up in bed. Then it passed and I felt good.
So how has it affected my training? The key difference is that I can ride for hours on very little food. By that I mean that I can go out and ride for 4 hours without breakfast and not eat, and not be hungry when I get back. I did a 7 hour 100miler on a 2 egg omelette for breakfast, a mini pork pie, a small cube of cheese and a few brazil nuts. I pushed really hard on what was a very hilly course and not only wasn’t hungry but also felt good at the end. I had a small snack about an hour later and then a good meal in the evening. I was also very impressed with how good my legs felt the following day. This is supposed to be due to the fact that burning fat is much “cleaner” than burning carbs; you do less oxidative damage to the muscles and therefore they should be less sore afterwards. I can agree with this so far, albeit it doesn’t work miracles!
In terms of strength, the power does seem to be in my legs. My heart rate has gone up at any given power; supposedly this is due to less vascular inflammation and therefore less resistance, meaning the heart has to pump faster. I don’t feel that I am working harder when this happens so the explanation makes sense. I’m not doing hard threshold or VO2max intervals at the moment. I suspect that these I would find harder but should improve in time.
I would be lying if I said that it was all plain sailing. So far I’ve had two major issues as a result of the diet change – in the interests of full disclosure I will mention both!!
The first issue is muscle cramps like I have never had in my life before. Before July, I could count on both hands the number of times I’ve had full-on cramp. Over the last two months it has become an almost nightly occurrence and so bad that I’ve spent the occasional night on the lounge floor trying desperately to stretch, roller, heat –just do anything to make it stop. No amount of hot baths or stretching seemed to be helping. Although able to perform when asked, my legs felt incredibly heavy most of the time, particularly my calves.
I had read that when you are taking in very low amounts of carbohydrates, you lose a lot more water through your kidneys and with it, a lot of salt. I had been told to increase the salt in my diet and although I’d done this, I obviously didn’t do it enough. After a particularly excruciating Friday night, I have spent the last few days adding an extra 2-3g of salt over the course of the day as recommended. Touch wood, the last couple of days seem a little better. My legs don’t feel quite as bad and whilst I did wake up last night, there was no actual cramp. Fingers crossed we might be getting there. I have also increased the amount of magnesium supplementation I’m taking as this can also be responsible for cramps and is something many people are deficient in.
The second major issue is a tad more delicate…. Let’s just say that if I was worried about GI issues during RAW, I have completely the opposite problem now; my guts have ground to a halt. There are many reasons this could be, possibly related to salt intake, magnesium balance, hormones…. Who knows?! I’m hoping that the changes I’ve made to increase both salt and magnesium will help. On the plus side it’s made me far more tolerant to caffeine ingestion (which from an endurance perspective will be very useful as even one coffee used to have a very stimulating effect on my guts previously which wasn’t helpful in the middle of a race!)
Do I have any treats? Absolutely! There has been the odd piece of apple pie and custard, some quinoa toast with almond butter (my absolute favourite) and the occasional cappuccino. This is a way of eating for life and whilst I need to stay generally low carb to stay fat-adapted, there is room for having a piece of birthday cake with a friend or a small glass of wine. I love food and life is too short to deprive yourself too much. That in itself places a stress on the body and mind which isn’t healthy or helpful. Intermittent fasting will also have its place to allow my body time to heal and regenerate. I’ve done this a few times already and find it quite liberating (and a lot easier than when I was fuelling with carbs).
So where now? I’m currently working with Peter Defty and the guys at VESPA, who specialise in something called Optimised Fat Metabolism. The rationale behind this is that carbs have their place and can be used strategically to increase performance. For example, before my 100 mile ride, I had some additional carbohydrate the night before. I also had some in my meal the night of the ride. Over the next few months I’ll be adding small amounts of additional carbohydrates before, during and after my rides and seeing how this increases performance. I’ve also been using a product called VESPA. This is an extract of a peptide used by a specific type of wasp which flies very long distances using only its internal fat stores; the peptide helps it access those fat stores and the logic is that it is a fat catalyst in people. I’ve only used it sporadically so far; sometimes it seems to have increased my performance and stopped me feeling hungry or flat on rides and other times I’ve not noticed a difference. As with anything, there are many day-to-day variations that can affect training and both actual and perceived performance. I will continue to experiment with it as there are good reports on its use and I like the fact that it’s natural.
Fat adaptation is very definitely a personalised journey. Whilst there are guidelines (and a few rules), everyone’s bodies behave very differently. Much of the science on it is based on its use in overweight people with Type 2 diabetes (or pre-diabetes) and whilst there are fat-adapted athletes succeeding in all sorts of sports at the top level, there isn’t the same range of scientific evidence that there is on more traditional fuelling. I’m generally pleased with how it is going, apart from the cramps and the GI issues. I think it will become easier as both my body and my mind adapt and we play around with my carb levels. I’d certainly recommend it, but only if you are prepared to be your own experiment. Now, where’s the cream…?