Lyle McDonald Interview: Flexible Dieting

Today I am so lucky to bring you an exclusive interview with the one and only Lyle McDonald! Lyle is a physiologist and author who is one of the top thought leaders in the fields of nutrition, fat loss and muscle growth. He has spent the past decade plus obsessively dissecting the latest research in order to bring the world unbiased information that they apply right away!

His site is his platform where he has hundred of amazing pieces of content using an evidence based approach to provide everything you need to know on the most important topics in this all encompassing health field.

And for those of you wondering, Lyle is arguably the creator of the phrase and dieting philosophy we all know as Flexible Dieting! He created his book, The Guide To Flexible Dieting all the way back in 2005! That’s crazy… We will touch on how much crap he got for writing this book in the interview.

Nonetheless, this is a value bomb loaded interview so dive into the material and be ready to learn a ton!

Lets get it started!

The Interview:

Me: Lyle! How are you doing my friend! Hope all is well!

Lyle: I’m doing well Zach! Looking forward to the interview.

Me: Ok lets get it started then!

Question #1: From my research, you were the first person to popularize the eating strategy known as flexible dieting when you published, A Guide To Flexible Dieting all the way back in 2005 which helped spur the movement which is not in full force. Since my readers are all either just now learning about flexible dieting or are currently flexible dieters but still want to learn more, what 3 tips would you tell them that would help the most to maximize their success along this journey.

Lyle: I actually think you’re correct, at least in terms of talking about it in any sort of formalized way or outside of the research. At the risk of being a little bit ranty, I wrote that book in 2005 and it went more or less ignored. Now in 2015, nobody can talk about anything else with endless “Guides to Flexible Dieting” and at least one case of apparent plagiarism where someone claimed to have pioneered the idea. Sorry, no.

I’m not sure I can actually come up with three tips about flexible dieting but I might go with this.

  • First realize that taking a flexible approach to dieting does not mean eating whatever and whenever you want. If your goal is fat loss or even health, being flexible (as opposed to rigid) simply means not taking the typical black/white, either/or, good/bad approach to dieting.People think in terms of foods as either diet or non-diet, good or bad and that’s a rigid approach. Adoption of flexible dieting attitudes, that is realizing that a single deviation from the diet doesn’t mean that you’re a failure or that the diet has failed, and that almost any food, within limits, can be included on a diet is the key to flexible dieting.
  • A second important tip is to realize that, no matter how rabid a lot of people are about flexible dieting, it’s not perfect for everyone. Dieting takes practice and folks who are often in the early stages of flexible dieting often find that a given flexible strategy throws them off the rails or doesn’t work for them. In that case, use it as a learning experience.
  • No approach is optimal for everyone and people tend to see any mistake as a failure in themselves. I’d say try any specific flexible dieting strategy three times, making adjustments based on whatever went “wrong” the first or second time and if it’s still not working, abandon it. A little ways down the road, when new habits have become more entrenched, they can be tried again.

Question #2: I love flexible dieting because it allows you to not only individualize your diet based on your needs but also allows you to model your diet around your current lifestyle. The best diet is the one you can see yourself doing for the rest of your life. Would love you to hear your thoughts on most restriction diets and why flexible dieting is superior?

Lyle: I’ll assume you mean dietary approaches that go from “This food is bad, NEVER eat it again.” It’s just human psychology why this tends not to work. Knowing you can’t have something makes you want it more. It also promotes the type of diet/non-diet food approach. Certain foods are what you eat on a diet and others are what you eat off a diet and this is a bad way to conceive of the process. Any fat loss diet should include foods and components that allow and promote long-term maintenance.

This type of “this food is bad” also promotes the same type of black/white rigid thinking that is the problem. It makes foods good or bad (often in a moral sense) and that’s just an absurd way to approach it. There is also the concept of never. It’s one thing for me to tell someone to wait 12 weeks (to establish habits) and then work on including previously problematic foods into their diet. But NEVER, who can survive with that approach.

Flexible dieting of varying types avoids all of this. Even knowing that, on occasion, in controlled manners that you can eat some food takes away the psychological stress from it. Never turns into sometimes or occasionally and that’s much easier to deal with in both the short and long term.

Question #3: On the topic of lifestyle, I work with a lot of entrepreneurs who want to adopt flexible dieting into their lifestyles. What do you think about flexible dieting for the busy entrepreneur?

Lyle: I don’t see why the concept would be any more or less relevant for any specific situation but in this, I could see it being potentially more useful. Many entrepreneurs, factually, do a lot of business over food or drinks. It’s just part of the job. And being a pain in the ass about what you can and cannot eat or taking a client out for drinks and then saying “I can’t have a drink as I’m dieting” is not a good way to facilitate those types of relationships.

Flexible dieting at least gives the potential to allow and plan for that. Schedule a free meal for that meeting, make adjustments at other times of the day to allow for it’s inclusion without derailing things in the long-term. You get the idea.

Question #4: An awesome benefit to flexible dieting is the idea of discretionary calories. It is the idea that if I hit my macros, fiber, and micronutrients, I can have foods like ice cream, cookies, and any other foods that most people classify as “dirty.” What do you think about this and whether there is any added benefit to going to 100% “clean” rather than fitting in these discretionary calories?

Lyle: One of the concepts that is relatively new and was not in my book is the IIFYM movement or If It Fits Your Macros. While this idea has been perverted in both directions, it basically came out of a reaction to the idea that the ONLY way to get lean is to eat CLEAN 100% of the time. Frankly, clean eating represents one of the most rigid approaches to dieting out there. Even the name alone, some foods are clean (morally) and others are unclean (morally). Eat clean foods and you are morally good, let even the tiniest bit of an unclean food cross your lips and you’re not.

At the same time, for people just starting out, IIFYM can cause more problems than it solves. Taste buds take time to adjust and while the IIFYMers are fairly rabid that everyone should be doing IIFYM, it simply doesn’t work for everybody. It’s one of those strategies that still requires control and some people get thrown off their diet with it. As above, try it a few times, if it doesn’t work, drop it. Dieting should always be a learning experience.

Question #5: Another big problem that many people encounter on their fat loss journeys is whether to cut calories significantly and try to lose weight fast or to make a small deficit and have a longer weight loss period. Would love your thoughts on both of those approaches and the pros and cons of each.

Lyle: Depends on the situation. Contrary to popular belief, the idea that big deficits always fail more is untrue; more rapid weight loss actually predicts better long-term success. There are probably a few reasons but even that is only conditionally true. Diets based around shakes, prepackaged foods, etc. do nothing to reteach good eating habits.

It goes back to their being diet foods and non-diet foods. Rather, extremely low calorie diets based around whole foods, exercise and behavior change are what show better long-term success. Because they focus on a diet that is based around whole foods, exercise has it’s major role for most in weight-loss maintenance and long-term behavior change is the key.

My own Rapid Fat Loss Handbook, a “crash” diet, is set up like this; it’s based around whole foods (protein, veggies, essential fatty acids) so that when the diet is over maintenance means adding foods back to that base, rather than switching to a completely different set of foods.

Now many have argued, and there is probably much truth to this, that smaller changes are more likely to be sustainable and lead to long term habits. I don’t disagree with this but consider someone with a hundred pounds to lose. A small change, unless it represents something pretty egregious is not going to generate weight or fat loss at any reasonable rate and this person is just as likely to become discouraged as anything else.

A decent compromise here, for the obese, is to use an extreme diet right off the bat to get some nice short-term weight and fat loss (which is psychologically rewarding) before moving into a more moderate fat loss diet in the long run. In contrast, for a lean dieter trying to get very lean, extreme diets, unless they are very short can cause problems with exercise performance and such. But there’s also not as much fat to lose.

So it’s a matter of context and both approaches have their place so long as they are properly implemented.

Question #6: So would you say that the more body fat you have, the higher your dietary fat should be? and vice versa for the leaner you are, the more carbs you can consume? And some thoughts on improving nutrient partitioning and how you can earn more carbs?

Lyle: Generally speaking, yes. There is a generally good correlation between increasing body fat and insulin resistance; it’s not universal mind you and you can find individuals at higher levels of body fat who show completely normal insulin sensitivity.

But in the first group, moderating carbohydrate intake and raising dietary fat can help avoid major blood sugar swings; there is also research suggesting that the obese respond differently to the fullness signals from the stomach than lean people do. I know that studies show that eating low glycemic index (GI) and lower glycemic load (GL) diets work for this too but, realistically, these aren’t the foods that most people eat in the real world. It’s usually just easier to lower carbohydrates and be done with it.

In general, there is a relationship between leanness and insulin sensitivity although it isn’t universal. Some lean people are insulin resistant too. By far and away the single aspect we can control to improve insulin sensitivity and carbohydrate tolerance (for lack of a better word) is training. And it has to be higher intensity training such as weight training. This improves muscular insulin sensitivity, depletes muscle glycogen (enhancing fat burning) which gives a bigger “sink” for incoming carbohydrates.

Question #7: If you have a client who says they are maintaining their bodyweight on 1000 calories and wants to lose body fat, what would your approach be with their diet?

Lyle: Tell them to track their diet because factually this is not happening unless they weigh 100 lbs. No study in the history of ever, outside of some severe disease states, has found someone with that low of a metabolic rate for maintenance unless they are absolutely tiny. In all cases, they are mistracking their food intake and that 1000 calories is really 2000 calories.

Question #8: You have a lot of information out there on helping people get rid of their stubborn body fat. Would love your thoughts on the idea that you cannot spot reduce body fat and that you just need to be in a caloric deficit for long enough to mobilize that stubborn body fat.

Lyle: Spot reduction is impossible. The idea that working a given muscle can burn off the fat on top of is it simply incorrect as there is no direct pathway from the fat on top of a muscle to that muscle. Body fat has to be mobilized into the bloodstream, under hormonal control, where it floats around until it gets burned (by the heart, muscle, liver or whatever) or gets stored again.

There was a recent study, actually, that almost offered a justification for spot reduction. It used something like 30 minutes of leg activity and for some reason, probably a local hormonal response some fat was mobilized. But it was in the mg range, it would have taken like a year to mobilize even a single pound of fat that way. Do 5 minutes of proper weight training and 25 minutes of aerobic activity and you’ve done more for fat loss than any 30 minute glute class.

So far as stubborn body fat, for men it’s usually just a matter of patience since abdominal and low-back fat is not as stubborn to get rid. Certainly there are strategies to help it along but the issue is that most men don’t realize how lean they have to really get to lose it. Sub 10% is going to be required and most men just give up.

Women’s lower body-fat is a whole different thing as it is profoundly stubborn to mobilization. It’s the last to come off and sometimes still doesn’t. There are various diet, supplement and training strategies that can be used to help with this. The physiology behind all of this along with strategies to deal with it are all detailed in my Stubborn Fat Solution.

Question #9: I am a huge proponent of making lean gains and staying in a small surplus in order to minimize fat gain while gaining lean muscle mass. What is your recommendation on how big of a surplus to be in order to optimally make lean gains?

Lyle: Depends on training status. A beginner can gain faster and handle a larger surplus, though it never has to be huge, than someone who is well trained. You might start a beginner with a 15-20% deficit, setting a goal of maybe 2 lb/month weight gain and an advanced person might use no more than 10% surplus (a few hundred calories) to start.

Question #10: Lastly, I wanted to get your take on low intensity cardio like walking in order to burn extra calories without beating you up and taking away from your training. I like to walk between 10,000-12,000 steps a day so I can eat more food to support my training. Would love your thoughts on this and if you think this is a good strategy.

Lyle: Despite a lot of nonsense that is being written about how cardio is ineffective (or at the idiot extreme, “makes” you fat), it’s been used for decades to get lean when combined with proper weight training and a diet. It’s easy to recover from, can be done daily and while it may not burn a lot of calories acutely, it adds up. Burn 300 calories from extra walking daily and that’s 2100 calories/week. Nearly 2/3 a pound of fat (not exactly) from an activity that won’t impair recovery.

The fascination with interval training is a mistaken one. Yes, it’s time effective, yes it generated nice fitness gains. It’s also very high intensity, exhausting if it’s done properly and can’t (or shouldn’t) be done daily. Yes, a combination of low-intensity work with the occasional interval session is great on a diet. Some can’t even recover from that. Since a lot of people who are dieting want to do some type of activity daily, you have to pick one that can actually be done every day. Low intensity fits that description, interval training does not.

Me: Well Lyle, that is all I have for ya today! I just wanted to say thanks again for being so generous with your time and the amazing answer you provided us today. You are someone I look up to and am truly honored to be able to share this interview with the readers! Wish you nothing but the best my friend!

Lyle: I enjoyed it! Keep up the great work and providing amazing content. I love to see young, go getters who want to make a difference in this field so I was more than happy to do this for ya! Talk to ya soon!

Homework Time!

Make sure to check out Lyle’s site! His site is a endless gold mine of amazing information so you’ll be smart to go check it out if you enjoyed this interview!

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