We caught up with low-carb expert Cliff Harvey to find out all about reducing carbs and why people’s responses to carbs can be very different.

What got you interested in low carb way of eating?
I initially got ‘into’ low-carb when I was studying nutrition at University in the 1990s. We were told to prescribe really high amounts of carbohydrate to clients (around 65% + of calories) and this just didn’t seem appropriate. Basically, I began thinking in depth about the roles of the macronutrients (carbs, protein, fat) in the body and as Carbs are pretty much just fuel, it didn’t make sense for people to have lots of carbohydrates, all the time, especially if they weren’t very active, or if they were not very tolerant of carbs because of ethnicity, genetics, and metabolic conditions (like diabetes and metabolic syndrome). As I delved into it, more and more, I began to see that when people were eating optimal levels of protein and fat, there simply wasn’t enough ‘room’ left for them to eat the ridiculously high amounts of carbs they had previously been told to eat. So, from about 1998 I have used and prescribed lower-carb interventions for myself and with clients ranging from Olympic athletes, through to those with chronic health conditions.

What is a carb appropriate nutritional approach?
‘Carb-Appropriate’ is a term I came up with back in the late 1990s to early 2000s. It is an approach to nutrition that recognises that people’s responses to carbs can be VERY different. Many people thrive on very low carb diets, most thrive on lower carbs than dietary guidelines say, and some people too thrive on high carb diets! Carb-Appropriate is about helping people to find out what they should be eating.

What are the benefits for performance athletes?
By figuring out their unique carb requirement, an athlete can develop what we call ‘metabolic efficiency’. This is when they use fat for fuel effectively AND still have sufficient carbohydrate stores to fuel higher intensity bursts of activity. By doing so, they can often endure longer, and take in less overall fuel during events, for the same, or better, performance gains.

What are the benefits for those with chronic illness?
Some of the most prevalent conditions that we see nowadays typically benefit from lower-carb diets. Metabolic conditions (like diabetes and pre-diabetes) benefit more from low-carb diets than from calorie restricted high carb diets, and because of this metabolic connection, many other conditions like Alzheimer’s (and other neural disorders), heart disease, and even cancer, can benefit from lower-carb diets.

What are the benefits for the everyday busy professional?
Many people suffer from energy crashes and brain fog. By learning to use fuel more effectively and produce fat derived fuels within the body, busy professionals and ‘weekend warriors’ can typically be clearer, more effective, focussed, and productive through the day. Not to mention that they can help to offset risks of metabolic conditions and dementia later in life!

How did you help yourself first adjust to a low carb diet? What is your advice to someone who is starting out?
I started doing this before it was really a ‘thing’! And so, I just leapt in and did a LOT of self-experimentation. I remember testing my blood sugar and ketones, playing around with various keto and other low-carb diets and doing all manner of ‘weird’ stuff twenty years ago! You can imagine what others in the industry thought of me!

Some of the key points to consider when starting low-carb though, are:
1. Drink more water than usual.
You don’t need to go crazy, but starting the day with 2 x large glasses, then drinking 2 litres per day (minimum) and an extra litre for each training session, should provide the extra water to replace what is inevitably flushed out of the body in the first 1-5 days of a low-carb diet.
2. Don’t restrict salt.
As above, the body also flushes out extra sodium in the first couple of days starting low-carb. Simply adding another couple of grams of sodium (i.e. one teaspoon extra per day of salt) is enough to offset this.
3. Eat LOTS of veggies.
A lot of people sacrifice veggies, especially if on a very low carb, ketogenic diet. But this is unnecessary. Keeping intake of veggies up provides few carbohydrates, but lots of vitamins, minerals, resistant starch and fibres (which actually help the body to become more ‘fat-adapted’) and especially potassium, which we also lose in the first few days of a low-carb diet.
4. Use coconut oil or MCTs to help produce ketones
Coconut oil and MCT oils help the body to produce ketones that can be used by the brain and body for fuel. These also aid fat loss by encouraging the body to burn more fat for fuel. If people are really struggling on a keto diet in the first few days, exogenous ketones are now also available, and these can be used when required for a brain and body boost.

What are the favourite resources you have used to learn more about the low carb diet?
I’m a nerd, so I basically just trawl through research papers! There are some great people in the industry to follow: Scientists like Jeff Volek, Stephen Phinney, Eric Westman, Annsi Manninen, Richard Feinman, Grant Schofield, and Caryn Zinn. I’ll also put my hand up there too! People can follow me and my college — The Holistic Performance Institute — for breaking info in the low-carb area.

What is your favourite low carb meal?
I actually LOVE smoothies. My favourite smoothie is:
4 x scoops Clean Lean Protein CHOC
1 x scoop Kid’s Good Stuff CHOC
3 x cups kale and spinach
1/2 cup blueberries
2 x Tbsp. peanut butter
1 x Tbsp. MCT oil
Simple, nutrient dense, super-fuel!

What are your thoughts on intermittent fasting?
Fasting is great! I was ahead of the curve on that one too. Way back in the very early 2000s, I had clients who were fasting for religious reasons but they were concerned that it might be detrimental to health. So I reviewed the research and found that fasting wasn’t damaging at all! In fact, it has many health benefits, from weight-loss to improvements in immune function, through to improved insulin sensitivity.

So, most people can benefit from fasting… BUT some people should be cautious. I am beginning to do research on certain conditions in which fasting can be detrimental. It’s always good to remember that what can be great for most, can be detrimental for some. For that reason, I always suggest that anyone wanting to make a drastic change to their diet should check in with a qualified, registered practitioner who is knowledgeable about low-carb diets and fasting.

Why do you think a low-carb diet is more effective than others for fat loss?
Low-carb diets are more effective for fat-loss for people with metabolic disorders and are typically more effective for early fat-loss than other diets. I think that a lot of the benefits can be traced to things more simple than what many assume. Low-carb diets overall, are typically more satiating (more satisfying) and so people tend to eat less overall. Behaviourally they also work more effectively than other diets for a lot of people. It is easier for many to abstain from foods (like high carb foods) rather than moderating them, especially if eating carbs drives them to crave (and eat!) more of them. There are other biochemical reasons too, but to be honest these are often misunderstood and are overstated. In a nutshell, low-carb diets work wonders for fat loss, but some people can still achieve the same, or greater benefits from higher-carb diets, especially if they are lucky enough to be very insulin sensitive!