Here is why cyclical diets (or "cheat days") work.
 

When you fast, restrict, or otherwise deprive and stress your body with fat loss, your body begins to immediately adapt by triggering a cascade of hormonal adaptations. Among these adaptations are mild hypothyroidism. This is known as "starvation mode".

Once you initiate a refeed, your body immediately begins to replenish its thyroid hormone levels to normal. This increases metabolism again.

So you see, by taking yourself down to low levels of intake, but then "jump starting" the metabolism with high cal/carb days, you avoid the adaption to starvation (hypothyroidism).

Here are some studies which offer some evidence...

http://jap.physiology.org/cgi/content/full/88/5/1820

http://www.ncbi.nlm.nih.gov/entrez/...1&dopt=Abstract

There's, I'm sure, lots more studies out there showing how fat loss and energy restriction causes hypothyroidism and other endocrine abnormalities.

Bottom line. If you're stalled and expressing symptoms of conservation (no energy, dry skin, shedding hair, zero libido & other indicators of fertility abnormalities)... try eating more. Eat more carbs and eat until you are stuffed for 1 or 2 days. See if that works.
I personally noticed during my weight loss (which was achieved mainly by restriction), on days where I would binge on meats were often the days I lost more soon after. Many people have also noticed this correlation. At first I thought it was psychological or behavioral or some other simple explanation, but I've now come to totally support and rally behind the theory that staggering calories (and carbs) really works for physiological reasons.

But what if you have real hypothyroidism? Do you think this approach will work (considering that I'm medically 'corrected' for my metabolism)?

thanks!

Hmmm... I don't think it is that simple. I don't produce thyroid hormone at all so I have to take it in a daily dose. Therefore, all my thyroid comes in very steady doses every day. Yet I still seem to get a slowed metabolism when I diet and can, eventually, stall for awhile. I know it slows because I get cold all the time and its harder to lose weight.

Yet when my doctor looks at my thyroid levels, they look fine.

Why would eating a low carb diet with adequate calories, trigger a starvation response? I would think this is only true if the appetite suppression you experience, leads to a very low calorie intake to the point where you ARE in starvation mode.

I am more inclined to believe what that Ellis fellow said, that people given license to eat as much fatty food as they desire, overeat and take in more calories than they can burn. And that this results in a failure to lose at the point where their lower body mass burns the same as their intake. I know from personal experience, that I can still eat like a 215lb person. But I'm not that much of a man anymore, so I am training myself to eat portions commensurate with my current weight.

One thing that jumping back and forth between carbs and fats as primary energy source might do, is to keep you from metabolizing the fats efficiently. The long-term response of increased enzyme production might never kick in if you keep your body thinking it is going back to carbs as the energy source. This may keep the "metabolic advantage" at its maximum.

One thing the carb cycling may offer, is a way for people who are mentally unprepared or otherwise unable to stick to low carb for life, to be able to utilize lc as a weight loss tool. Knowing you can have your carby foods now and then, probably is a lot easier to live with for many folks.

I looked a the two studies you cited, and both of these were dealing with true semi-starvation diets right? So we are making a real jump, to assume that someone who is stalled is in starvation mode. Not saying it cannot happen, but I do think that the greater tendency, is to overeat the high calorie foods that are allowed in "unlimited amounts". At least that is my experience. Fortunately for me, I didn't hit a real plateau till I was nearly to where I wanted to be.

FOr a lot of us overweight folks, our eating habits include eating a large quantity of food. Now when we eat high-fat and low carb, we naturally get and stay full quicker. But I think some of the old habits can still bleed through this barrier to overconsumption. When you are used to eating a large volume, there is more to breaking that habit than just satisfying hunger. In fact, I don't think hunger was that much involved when I would scarf down 6 doughnuts at work.

Not saying the carb cycling isn't a tool to consider, just that the principles underlying its utility may or may not be explained through disruption of a semi-starvation state.

This is interesting... I've also noticed that I seem to have my best weightloss when I eat a lot of meat.

Nancy LC, can I get more information from you about your eating habits, g carbs/day, # calories, etc. Since we are both hypothyroid, I am encouraged by your success (Congratulations!) and would love to learn about how you accomplished it!

I've been very discouraged over the last 4 yrs, not being able to lose weight as a hypo, but you're proving it can be done. Any tips w/stalls, ideas for how much weight you typically lose/week or month, I'd really appreicate!

I agree with Wooo. Our bodies are amazing at adapting to all sorts of conditions. Although we may not understand all of the mechanisms, it is clear that we can adapt to certain diets with metabolic and enzymatic changes.

Carb cycling didn't work for me personally, because once I up my carbs it triggers cravings and I have a hard time getting back on plan. But if you can do it, I think it works.

Studies have shown that most people on low carb do eat less calories than they used to, even if they're not trying to. So an occasional cheat day should counteract the metabolic drop from eating less calories.

im gonna have to agree with that

For It's The Wooo--When you say "high carb/high cal days", do you still avoid sugar and refined flours on those days? Just trying to make sure that I understand the idea completely. For instance--on those days, do you just eat more of the whole foods such as veggies--even the starchy ones, and more of the normally allowed treats, etc.? I have to agree also, that the "meatier" days seem to leave me with a greater loss afterwards. :D

I completely agree with this. I've stayed very strict for a long time because it's done such wonders for my health, but I have noticed a few things:
-I have to watch calories now to lose weight, and keep them at a similar range that I used to aim for on low-fat,
-I have lost the "Atkin's breath", that ketone smell in general, I just don't seem to be excreting them all over the place like I did when I first started.

So I suspect that after 2 years my body has become extremely efficient at burning fats and that I have lost any "metabolic advantage" I used to have. I don't mind terribly, but if weightloss was my primary goal I would definitely feel a lot more frustrated. I'd like to lose faster but I haven't tried carb cycling because I'm worried about the effects of jerking my insulin levels up and down periodically.

Hmmm... I'm not sure you can say I'm hypothyroid really. My thyroid levels are normal because I take daily thyroid medication. But I do lose weight very slowly and I must cut calories to do so. Are you getting your condition treated? aka taking thyroid hormone?

Also, when I had Graves Disease, which is hyperthyroidism, I actually GAINED weight! Kind of paradoxical, but there you go. My doctors were surprised but said it wasn't unheard of just not usual. I don't think I ate an abnormally huge amount, but I was eating probably a pretty normal American diet, without sugary pop. You'd think someone with a resting pulse rate of 120 would be burning calories like mad.

For me, I have to keep my calories to around 1300-1400. I don't know that carb grams matter so much for weight loss, but I try to keep them 20 or fewer during the week. On the weekends I party with about 1600 calories and about 40g of carbs. I don't cheat, I don't have cravings or fall off the wagon. The lower carbs keep the appetite in check.

The only way I seem to lose weight is with calorie reduction. And my typical rate of loss is very, very slow. I've been on low carb for 1.5 years and have only lost around 35 pounds out of the 50-60 I need to lose. I find that I have to be very strict with calories otherwise I just maintain.

BTW: Part of the time after my thyroid was removed I was severely hypothyroid, they were waiting for my body to use up its stores so they could properly dose my thyroid hormone. And I was on Nutri/System at the time, exercising about 1 hour a day, eating 1200 calories a day and I totally stalled out for weeks until they got my thyroid dose right.

So my body has two rates of losing weight.... imperceptibly and extremely slowly. Make that three: Not at all. There's only one way to deal with that... time. Over time it does go. Patience is the key.

Nancy, thanks for your words of wisdom. Yes, I am on Levoxyl (137ug)..and have been at that level for almost 1 year. So, my hypothyroidism is in 'check', but I've been on the 1200-1300 cal diet w/exercise at 5-6x week (carbs probably around 150g) and either gained or maintained.

Starting Atkins now I am not really losing weight, I've lost a few inches here and there, but I managed to lose 10 on CAD just before switching to Atkins. I do feel better on LC WOE, but I still need to lose 15 lbs (am insulin resistant and don't want to tempt my body w/diabetes). After trying for 4 yrs to lose and not being successful, I DO want it to happen overnight (still would like atleast 1 WOOSH!)...but I agree w/your statement about patience.

I'm in a 4 week stall w/the scale, and it's getting harder to be patient when I feel like I'm just maintaining vs losing. Want to get the scale going again!

Just to throw my cents in, I tend to agree with its the Wooo based upon my experience. Please keep in mind I have had my thyroid checked and the values register normal, even though my body temp stays around 96.6 most days. I had been at 1200-1300 cal 20carbs exercising 45minutes daily and lost 3 lbs over 6 months. Those were lost when I actually increased my claories a bit sporadically to 1500-1600.

In addition, I was unable to exercise as I had been after a recent surgery and even keeping my calories at 1200 20 carbs with a daily 2 mile walk I gained 1.5lbs. that I am wokring on losing now that I can exercise fully again.

Finally, years ago when losing dieting strenuously, I lowered my daily intake to 500 calories an dmaintained my weight on that for several months (of course I was very unhealthy) but actually had to gain weight (10ish lbs) before I was able to improve my metabolism.

Th point, our bodies are very adaptable, some more than others. In times of famine this would be a great asset, but not so good when trying to lose weight and unfortunately your body does not recognize the difference.

Kristen

Kristen wrote: "In times of famine this would be a great asset, but not so good when trying to lose weight and unfortunately your body does not recognize the difference."

But we need not be in starvation mode when we lose fat off our bodies! In fact, this is detrimental to weight loss in the long run. We are simply eating the way we were meant to, and a normal apetite (and as a direct consequence, body fat level) is a natural result. When you eat low carb and take in a reasonable number of calories, your body doesn't think its being starved. It thinks what is supposed to be a realtively short "high carb season" is over, and its time to use fat for energy.

But not everyone can lose weight that way, Tom. For instance, if I give my appetite free reign, even on Low Carb, I will not lose weight. I might even gain a tad. I've tried this for 8 months on end, it simply doesn't work for everyone. I'm not even close to what I should weigh, which was around 130 in my 30's... I'm giving myself a free 10 pounds because I'm in my mid-40's now.. I earned it.

I realize it seems odd, it does to me too. Why do some people fail to lose weight at very low levels of calories? Are they impervious to starvation? That isn't possible... obviously given enough time they'd starve to death. But people can live a long, long time without eating... if I recall correctly its about 60 days or so. I doubt anyone came out of a concentration camp fat even though they were starved.... So why can't people on moderately low calorie diets lose weight sometimes? What is going on?

Its just weird.

I think (calorie staggering and period refeeding) will help even those who are thyroid hormone dependent, and I'll explain why. Raw thyroid hormones aren't the end-all be-all of the thyroid. Even if you are taking adequate doses of synthetic thyroid hormone, if you are in a highly catabolic state (starvation), the hormones will not work properly.

As the first study I cited reported, thyroid hormones are only one half of the picture... how well they work also depends on cofators namely insulin and IGF (insulin-like growth factors). They bond to the thyroid hormones, thereby making them active and bioavailable.

WHen you trigger rapid catabolism whether by simple severe calorie reduction or a super low carb diet, insulin and IGF plummet to accomodate. This then reduces thyroid hormone potency, by resulting in less bioavailable thyroid hormone. Basically the human body has evolved over time to associate at the hip catabolism with an automatic lowering of thyroid output. Even if you're taking synthetic hormones, if you're insulin and IGF is kaput because you're practically starved, your not going to be using much energy for fuel or anabolism. In normal people with normal thyroid functioning, eating more food and sugar after prolonged deprivation will bring everything back to normal. In synthetic thyroid hormone dependent people, eating more will allow the hormones to actually work better.

That's my theory, anyway.

Here's some personal anecdotal evidence of the starvation/restriction/fat loss causes stalls because of reduced thyroid functioning.

When I was at the height of my restrictive dieting, I was consuming roughly 1100 calories per day and eating rather low carb (not ketogenic, but close). I exhibited numerous signs of adaption to restriction and thyroid insufficiency.

My basal temp routinely came in at low 97, high 96. The max I would see would be high 97. It almost never got above 98 degrees.

Flash forward to today. I now eat 1500-1600 calories daily, and all indicators of energy conservation are getting much better (for one, muscle anabolism has increased dramatically, energy levels are better, I am no longer as cold sensitive, I am much more capable of naturally regulating food intake (i.e. I no longer have that famous starvation/weight loss induced screwed up hunger/satiety signaling).

I just took my temp with the same thermometer. Of three readings the values were as follows:
98.2
98.1
98.2

Much more close to normal.
Keep in mind the only thing I really changed was the quantity of food I've eaten. If I eat more calories and carbs, I likely could improve things more (as well as improve my perception of energy, well being and general health which still aren't ideal, although they are SIGNIFICANTLY better than they were before when I was restricting calories).

The only way to catabolize body fat is by triggering an energy deficit some how. Low carb is not absolved. YOur body doesn't care how this energy deficit is being made. Some methods are more extreme than others (e.g. doing a semi-fast is much more extreme and hurtful to the body than smaller modest caloric deficits). Eventually, though, the toll is the same. The only differences between the approaches is how long it takes to get into this state. Persist in fasting and within days you'll be conserving lots of energy. Do a "sensible diet" with no brakes that results in stead weight loss, and after a couple of months you'll be where the faster was within a week.

We are the products of thousands of years of selection. Your body is not stupid. It is designed to regulate and conserve tissue stores to ensure survival. If these are being depleted, it will try to protect itself. The starvation response is dependent exclusively on the difference between energy available for use (both on the body and from diet), and the actual need for energy. If you are losing weight, you are creating an energy deficit. Your body doesn't care if you do it slowly and more healthfully with atkins or if you're a mentally disturbed anorexic. The only difference between the methods is how soon and how severe your symptoms will be.

I do agree that a lot of people who stall out on Atkins are simply comfortably eating to complete fullness, enjoying that satisfied feeling of being "stuffed" after a meal, etc.

Not always, though. Relative to how little I was eating, I wasn't losing that much weight. I even entered ketchup and onions in fitday, and I always overestimated serving sizes. I don't think over eating was the culprit for me in so much as energy conservation was. Don't get me wrong I was still losing, however it was slower than it should have been for a healthy person.



I do think it has psychological benefits as well. This was my original theory.

However, in my own personal experience, I really think there's more to it than that.
It's also more than a long term enzymatic shift, since the results of calorie staggering are immediate and appear within days (as my experiences, and the studies suggest). Technically if you were stalled due to an enzymatic adaption to using a certain kind of energy, the staggering part wouldn't work. Changing your diet back to a higher calorie, higher carb would.
Also, more evidence against the theory is that when people do carb and calorie staggering, it's mostly calories that are changed. Carbs are barely changed at all. In my case, I eat slightly more carbs but way more calories.

I'm not saying these other factors don't exist (psychological factors, avoiding making enzymatic adaptations to a fat based metabolism), I merely think they are less significant than the thyroid connection.

You know, you gave me an idea. Maybe the thing that should trigger a "carb up" is one's temperature going down. Hm... that's an idea.

I lost my weight on 1500 calories a day, ALWAYS (well almost) having a 'free day' on the weekend. I started out with two free days (back when I was 168), and cut it down to one. I still do it, and eat a clean 1800-2K calories the rest of the week. I think it helped me from dropping my metabolism down too low so I can maintain at 120-something and have 1800 calories+/day. Keep in mind, however, that while I was lowering carbs, my weight loss phase still was 40% carbs so a carb count didn't effect me either way.

My free days aren't binges, but they are pretty durn free. :) (and considerably higher carb/fat/calories :P)

Woo - I logged into your fitday and I noticed something - we are similar in size and I noticed your daily calorie expenditure was much lower than mine. I think you have it set up for being bed-ridden! Just noticed because we are similar in size, and don't know if you care, but thought I'd point it out

Anyhow, sorry to go OT, carry on!

Hi runnr,
Yes I set the calorie expendature for bed ridden. IMO fitday's lifestyle calorie estimations are far too high.

I don't really use fitday anymore, but when I did I found it to be much too generous.

I don't think that either study has any meaning in regards to a low-carb lifestyle. The first study was done on army Rangers during heavy training in which they had a greater than 2000 Calorie deficit. The second was on obese females on 300 calorie diets. No low-carb diet that I am aware of suggests that you restrict calories to such an extent. Both studies show that starvation is not good, but we knew that anyway.

ItsTheWoo, I always enjoy reading your posts... totally helpful and interesting. You're an inspiration to us all: Brilliant, beautiful, and will power of steel.

I have noticed as well that if I'm stalled and exhibiting unhealthy body signals that eating more for a couple of days usually gets my system going again.

When I have my up carb days, I eat a low carb candy bar, or some fruit, an extra low carb tortilla, never real sugar, pasta, potatoes, corn anything like that, I do snack on popcorn every now and then. After I eat like this a couple of days, then go to low carb "induction levels" I do start feeling better and losing fat or water or something, because I feel better. My skin is a mess, I am so dry, and my face is breaking out, so I had a couple of up carb days, and now my face is clearing up, and I am getting better skin too!! I guess it just depends on the person!! I can handle the cravings, because of all of the success I have already had.