The other day I wrote to someone I highly respect, Dr. Barbara Berkeley, MD, author of an excellent weight maintenance blog (Refuse to Regain) and a book of the same title: Refuse to Regain!: 12 Tough Rules to Maintain the Body You've Earned! Barbara is a doctor who has specialized in the care of overweight and obese patients for more than 20 years. The email conversation we had was interesting and enlightening, especially given the struggles I have had to get weight off lately. I've been trying to cut my carb intake to 100g/day or less, but wondered if this was a wise choice given the success I had with Medifast on that carb level but the quick regain when I reintroduced carbs to my diet. With her permission, here is part of our exchange.
I have been reading a bit about reducing carbs significantly for weight loss. I wondered if you think that being in some state of ketosis (deep or mild) is important for efficient weight loss. Also, once one is in maintenance, do you think that changes? I ask because although I have lost and kept off 60+ pounds over the past five years, at one point I was down over 100 pounds and I have regained back 40ish. I was on Medifast in a state of "mild ketosis" at 900-1000 calories and 80-90 g carbs/day to lose that last 40. When I stopped Medifast and began to eat more carbs, the weight came back very fast. I have been trying to re-lose without being in ketosis, but wonder if you think that state would be better in the long term. I just worry about any health effects of being in ketosis long term, such as being unable to keep the weight off while eating a reasonable amount of food at maintenance. Any guidance would be appreciated!
It's not necessary to be "in ketosis" in order to either lose weight or maintain it. I don't advocate the use of ketosticks or any other method of monitoring ketones. Our patients lose large amounts of weight without showing ketones in the urine, so don't worry about this measure.
I think a better way to look at this is to say that you want to remain in a state of "keto adaptation". This is a term coined by researcher Stephen Phinney and what it means is that you want to keep your body in a state that preferentially burns fat over sugar. In order to do this, you have to keep carb consumption very low permanently. The key phrase in your email is: when I 'began to eat more carbs, the weight came back very fast'. This is what I see over and over again.
Your body is like a hybrid car that can run on one of two fuels. Sugar or fat. In America, we all run on sugar. Running on sugar produces insulin and insulin both promotes fat storage and prevents fat breakdown. Thus, once you start with carbs again, you will store fat and not be able to lose it. I also think that people who have been heavy in the past have a broken insulin system. They are exquisitely sensitive to carb consumption and it quickly boosts insulin levels in a way it might not with NOW (never overweight) people.
My advice would be to go back onto medifast to knock off some weight. After you've done that, I would meticulously document your critical carb level. This is a term Atkins used and I like it. For me, my CCL is about 100 grams/day. Any more than that and I will gain. It might be different for you. I would experiment with adding back only the carbs you REALLY need and see where you stabilize. Remember that grains, even whole ones, are carbs. Don't fall prey to them.
I'm currently reading The Art and Science of Low Carbohydrate Living by Phinney and Jeff Volek. I recommend it as something you might want to look at.
In the exchange that followed, I asked Barbara another question:
In maintenance, do you think you (personally) are still in a state of burning fat over sugar? And if so do you need to eat a higher percentage of healthy fats for fuel, rather than increasing carbs?
The answer for me is that I eat fats but try to keep them modest because of the calories. If you eat extremely minimal carbs, fats are fine. I try to choose healthy fats, meaning the fats from fish and animal products that are well-raised (without grain) if possible... Remember that if you are basically a fat burner, your body always has access to about 40,000 calories available in energy (that's what is in your fat stores)! You only need about 2000 a day to run everything!! There is no need to increase calories to get fuel. The problem is that the body cannot get into that fat bank when you are making a lot of insulin. Instead, the body uses your sugar bank, which is only capable of storing about 1200 or so calories. If you're running on sugar, when that 1200 gets low, you are in your pantry looking for carbs. Cut the insulin and you will have more than enough to "eat".
I think she is right. I believe the key to getting this weight back off AND keeping it off has everything to do with the level of carbs I ingest. I know this is not the answer for everyone. Lots of folks eat plenty of whole grains and fruits and stay a healthy weight. But I think my years of binge eating sugary, carby junk really did mess up my insulin response. I believe it is essential for *me* to get under, and stay under, the critical carb level mentioned. How to do that... well, that's another post.