- microwaving a pint of Ben & Jerry’s and downing it in a matter of minutes
- or ordering cheesecake at The Cheesecake Factory for both the dinner and dessert courses
- or eating leftover homemade chocolate cake for breakfast.
That used to be me. (Biggest sweet-tooth of anyone you’ve ever met, I swear.)
I grew up with the idea that carbs were fuel. That conventional wisdom of the day informed my understanding of how to provide my body with the energy I needed.
As a competitive athlete during my university days and throughout much of my twenties, I regularly trained up to three times a day, which left me with a sizeable appetite.
The night before a race I would routinely "carbo load” along with my teammates, gorging myself on pasta and bread. (Back then, I clearly didn’t give as much thought to the quality of the carbs I consumed as I did to the quantity.)
I’ve always felt fairly fortunate as I seem to have a pretty strong stomach compared to some others and can eat just about anything without feeling ill.
(Case in point: I was the first woman to successfully complete the Pizza Two Mile 'fun run' at my university, which involved running eight laps on the track as fast as you could while consuming eight slices of cheese pizza…and keeping it down. Good times.)
One of the (many) benefits of my sports background is that it left me pretty attuned to what my body needs and wants. As I got older and my activity level lessened, my cravings for sweets decreased to the point where you’d be more likely to find me eating organic, whole foods at Little Bird then downing donuts at Krispy Kreme. (I was still fuelling myself with carbs, just fewer - and arguably healthier versions - of them.)
Throughout my life, from doctor’s perspectives, my blood work and physicals have always revealed me to be in stellar health. My weight's been stable, my sleep is consistently good and - a couple high-stress periods aside - I feel generally well. Why change anything?
Staying Curious - Personal Experiments with Nutrition and High-Performance
As someone interested in high-performance in both the personal and professional contexts, I am regularly experimenting with the tools and techniques I come across in the research I read or that I learn about from others as being performance enhancing. Floating? Journaling? Managing Heart Rate Variability (HRV)? I’ll give it a try.
For various environmental, moral, and performance enhancement-seeking reasons, I have over the years experimented with what I eat as well. I’ve tried eating gluten-free, dairy-free, vegetarian, vegan, even intermittent fasting.
In my personal experience, the impacts of any of those dietary changes on my performance felt fairly nominal, which ended up reinforcing my view that I must have a ‘strong stomach’ and can simply eat whatever I want without it having any substantial effect on me.
But when my partner came home one day and mentioned that a brilliant, high-powered colleague of his had sworn by a ketogenic diet for the past two years and attributed her high levels of energy and mental performance to it, that got my attention.
I immediately started researching what ketogenesis was all about and came across numerous studies indicating that contrary to the belief I’d held (that carbs are the body’s preferred source of fuel), there is another, even better source of fuel our bodies can run on - fat.
I got my partner’s buy-in to trial the keto (Low Carb, High Fat (LCHF)) diet together for at least four weeks, purchased a blood ketone meter to measure our ketone levels, drew up a ketogenic meal plan, went shopping for the necessary ingredients and selected an appointment-free weekend to start our diet on (in case either of us ended up with a bad case of the keto flu).
If you are interested in the details of my experience with the diet to date, you can find that in the diary entries below but in summary, I’ll simply say that I’ve been blown away by the impact this dietary change has had on how I perform, feel and even look.
The Lesson - Challenge Your Assumptions
Now, you might think that the purpose of this article is to simply convince you to 'go keto'...but it’s not.
If you take anything from my story, I hope it’s the importance and value of challenging your assumptions from time to time (even long-held assumptions like mine) - being open, curious and willing to experiment to see what works for you, rather then simply resting on the belief that you already know best or blindly accepting that the advice you got from someone else must be true for you, too.
What’s an experiment you could try to challenge one of your assumptions?
You just might be surprised at the results.
*Disclaimer: The information in this article is not intended as medical advice. It is intended as the sharing of knowledge and information from the personal research and experience of Aenslee Tanner. You should consult with your doctor or other healthcare professional before starting any diet to determine if it is right for your needs.*
My Keto Diary (up to the time of writing this article)
- DAYS 1 & 2: Started with a 16 hour fast from Friday evening to Saturday morning. Started high-fat, moderate protein, low-carb (<=20 net carbs/day) diet on Saturday. Normal spin class performance on Saturday morning. Felt cranky and had strong carb cravings all weekend. Slight repulsion to eating the fatty foods. Frequently thirsty and light-headed.
- DAYS 3 & 4: Experiencing euphoria, no feelings of hunger or fullness, carb cravings reduced slightly. Less resistance to eating the fatty foods, clear concentration, strong focus, increased stamina on the spin bike. Not tired, hard to sleep.
- REST OF WEEK 1: Feeling tired. No feelings of hunger. Fewer skin breakouts. Notice belly stays flat (no puffiness) after meals.
- WEEK 2: Increased stamina in spin class continues (no ‘dying’ at end of sprints, recover quickly, pulled a muscle from being able to push so hard on the bike!). Mental state feels like it’s returned to normal. Feel tired at bedtime as per normal. Carb cravings fluctuate but minimal hunger (now down to two meals a day). Body felt heavy during run. Frequently thirsty. Notice red spots (keto rash) on sides and front of torso. Eczema reduced.
- WEEK 3: Great stamina in spin continues. Feel light-headed and thirsty when haven’t eaten recently. Keto rash still there.
- WEEK 4: Feeling clear and energized. Great stamina in spin continues. Craving carbs towards the end of each day. Keto rash still there. Reduced inflammation in joints.
- WEEK 5: We went on holiday this week so decided to test out our metabolic flexibility by eating out/going back to a higher carb diet. Splurged on carbs on the first day of this week and ended up with a puffy belly and sore tummy. Noticed reduced mental clarity and less energy but also a reduction in keto rash. Immediately craved going back to keto diet so restricted foods to high-fat/low-carb as much as possible while on the road starting from day two of this week.
- WEEK 6: Great stamina in spin continues. Often thirsty so drink water constantly. Keto rash back more prominently than ever and starting to itch.
Summary of benefits:
- Greater mental clarity, stamina, and focus
- Greater physical stamina during training
- Reduced inflammation in joints
- Clearer skin/fewer breakouts
- Reduced eczema
- Reduced feelings of hunger (plus time saved from reduced meal times)
- No crashing of energy (ie blood sugar levels are stable all day long)
- No belly puffiness after eating
Summary of challenges:
- Keto rash
- Fluctuating carb cravings
- Changing social and emotional habits (eg going out to cafes/restaurants is difficult because just about everything on the menu is high in carbs; struggling to reprogram how much food is tied to social and emotional rituals (celebrating over a meal or with a cake, baking to show caring, etc))
As for my next steps in this experiment, I’m planning to:
- Head to the doctor for a blood test to make sure my results are still healthy given my significant change in diet
- Experiment with increasing carbs to 50-100/day and add in intermittent fasting to try to address keto rash
Further information on the ketogenic diet can be found here: