[ladyinweighting]

No-Carb Diets May Impair Memory
Memory Improved When Carbs Reintroduced to Diet
By Salynn Boyles
WebMD Health NewsReviewed by Brunilda Nazario, MDDec. 12, 2008 -

Eliminating carbohydrates from your diet may help you lose weight, but it could leave you fuzzy headed and forgetful, a new study suggests.

One week after starting a weight loss diet that severely restricted carbohydrates, participants in the Tufts University study performed significantly worse on memory tests than participants who followed a low calorie, high-carbohydrate diet.

The low-carb dieters' memory-test performances improved in the following weeks after they began eating some carbohydrates.
"The connection between the foods we eat and how we think doesn't really enter into most people's minds," study co-author and cognitive psychologist Holly A. Taylor, PhD tells WebMD. "But this study demonstrates that the foods we eat can have an immediate impact on brain function."

Carbs Are Brain Fuel
The body breaks carbohydrates into glucose, which it uses to fuel brain activity. Proteins break down into glycogen, which can also be used for fuel by the brain, but not as efficiently as glucose.

So it stands to reason that eliminating carbohydrates from the diet might reduce the brain's source of energy and affect brain function. But there has been little research examining this hypothesis in people following low-carb weight loss diets.

The study by Taylor and colleagues included 19 women between the ages of 22 to 55 who were closely followed after beginning a low-carb weight loss plan similar to the Atkins diet or the low-calorie diet recommended by the American Dietetic Association that includes plenty of fruits, vegetables, and whole grains.

Before starting the diets, the women underwent testing designed to measure long- and short-term memory and attention. The tests were repeated one, two, and three weeks after the diet began.

Low-carb dieters ate virtually no carbohydrates during their first week on the diet. In testing conducted after week one, they performed worse on memory-based tasks than the women following the ADA diet.

Reaction times for those on the low-carb diet were slower and their visual-spatial memories were not as good as the low-calorie dieters.

They did perform better than the low-calorie dieters in testing that measured attention and the ability to stay on task, however.

And their performance on the memory tests improved after week one, when limited carbohydrates were reintroduced into their diets.

"Although this study only tracked dieting participants for three weeks, the data suggest that diets can affect more than just weight," Taylor notes in a news release. "The brain needs glucose for energy and diets low in carbohydrates can be detrimental to learning, memory, and thinking."

The study is published in the February 2009 issue of the journal Appetite.

More Study Needed
Australian research scientist Grant D. Brinkworth, PhD, tells WebMD that the findings, while intriguing, do not prove that low-carbohydrate weight loss diets affect memory.

In a study published in 2007, Brinkworth and colleagues performed cognitive function testing on dieters after they had been on either a low-carb or high-carb weight-loss diet for eight weeks.

Both groups lost weight and showed improvements in mood.

The low-carbohydrate dieters showed slight impairments in cognitive processing speed, but no difference was recorded between the two groups in working memory.

Brinkworth says if eliminating carbohydrates from the diet does affect memory, the effect may only be temporary.

"What (Taylor and colleagues) recorded may be an acute, transient effect that may just be the body readjusting to an unfamiliar diet," he says. "We really need studies that examine the long-term impact of these diets on cognition."

Calls to a representative from the private equity firm North Castle Partners, which owns controlling interest in Atkins Nutritional Holdings, were not immediately returned.

[JayEll]

The brain has to have glucose, period, and if it's not available, the body converts protein (muscle, connective tissue, etc.) into glucose first. That's why "NO carb" diets (or total fasting, for that matter) are not a good idea.

The LOW-carb diets generally include sufficient carbohydrate in a complex form to avoid the breakdown of protein, an effect called "protein-sparing."

Jay

[JerseyGyrl]

Originally Posted by ladyinweighting

The study by Taylor and colleagues included 19 women between the ages of 22 to 55 who were closely followed after beginning a low-carb weight loss plan similar to the Atkins diet or the low-calorie diet recommended by the American Dietetic Association that includes plenty of fruits, vegetables, and whole grains.

Before starting the diets, the women underwent testing designed to measure long- and short-term memory and attention. The tests were repeated one, two, and three weeks after the diet began.

Low-carb dieters ate virtually no carbohydrates during their first week on the diet. In testing conducted after week one, they performed worse on memory-based tasks than the women following the ADA diet.

Reaction times for those on the low-carb diet were slower and their visual-spatial memories were not as good as the low-calorie dieters.

They did perform better than the low-calorie dieters in testing that measured attention and the ability to stay on task, however.

And their performance on the memory tests improved after week one, when limited carbohydrates were reintroduced into their diets.

I wonder when, or IF any of these studies will ever use ACCURATE information to base their claims on

Atkins is NOT a NO CARB diet. Atkins is a LOW CARB diet. Most people are absolutely shocked to learn that the Atkins lifestyle advocates fruits, vegetables & whole grains! Yes...I said ATKINS!!! The initial phase of Atkins (Induction) is strict, the purpose is to rid your body of sugar cravings by limiting your carbs to 20 a day with the emphasis of 12-15 of those 20 carbs coming from VEGETABLES! In the following phases of Atkins, fruits, starchier veggies, as well as whole grains are slowly added back to your diet. This is the way Atkins is done CORRECTLY!

I'll be on Atkins 5 years in a few months...I don't think I'm fuzzy headed or forgetful...but, then again...I eat carbs!!

[kaplods]

I think the induction or first phases common to carb-controlled diets are given much more attention than they deserve. They're so often taken out of the context of the plan, both by outsiders and by those following the plan, that sometimes I think they do more harm than good, and some of the plans would be better off without them.

Although reducing cravings is often given as a justification, I suspect the stronger motivations are actually psychological, starting with the fact that "jump start" components are extremely popular. Most folks can follow any plan for about two weeks, so a plan that has a very restrictive initial phase has two psychological advantages over a plan that does not. The first - it usually results in a fairly dramatic weight loss, proving quickly that the plan "works." Second - the continuing phase is so much less restrictive than the first that there's an emotional relief and a perception that the continuing part of the plan is easy (because in comparison to the first stage it is). Most of the plans allow the dieter to continue or return to the most restrictive phase (appealing to the obsessive dieter who wants to see rapid results) and the more balanced portion of the plan to appeal to folks who are attracted to a more balanced approach.

I know that what I'm saying is almost sacreligious, but I don't think there is any magic to the jump start phases, and instead their existence only adds fuel to the fire for those critiquing the plans. Atkins never tells you where most people will stop (in terms of carb count during weight loss or at maintenance) - because the theory is that the ideal carb level will be unique to the individual. I believe there's something in the book about where "most folks" will stop, but there's nothing about what the range could be. That means, in theory, that some folks could be eating 100g of carbs or even more and still be following Atkins to the letter. So how does one evaluate in a study a low carb diet that for some participants would not be low carb at all by some standards , but one in which each of the participants are consuming differing amounts of carbohydrates?

Many of these plans are written by doctors who have developed them using real patients. And in the real world, with real patients, there's a conversation between patient and doctor that the book cannot provide. A patient following a jump start phase who is having uncomfortable symptoms - would probably be encouraged by the doctor to move on to the next phase. A patient who was feeling great in the jump start phase and not wanting to move on, might be encouraged to continue if they'd like to as long as they're feeling good. Without the doctor though, some people may experience horrendous side effects, but be unwilling to move on to the next phase of the plan because they don't want to give up the rapid weight loss. Then when they can't handle the unpleasant effects anymore, they quit rather than move on to the less restrictive stages of the plan. Then there are those who aren't reading the book at all, or aren't reading carefully, and don't understand the plan before they start. How can you evaluate a plan based on the experiences of subjects who are not really following the plan because they don't understand it?

I think the poor research designs of many weight loss studies, reflect that we are still in the "dark ages" in terms of understanding obesity and effective therapies. We're asking the wrong questions, and it's not surprising that the answers don't make much sense.

[kris2008]

I guess everyone's different. My brain works much better on low carb. If I'm on really low carb, I feel like I've hit a wall - brain and bodywise. My cravings are high carb and my brain doesn't work as well. If I can stay awake.