(NaturalNews) In a study comparing an Atkins-type diet with a reduced-calorie regime, Tufts University scientists reported that low-carb diets may impair cognitive performance (D'Anci 2009). Since glucose is the brain's primary fuel, the need for it may not be met when restricting carbohydrates.
Granted, some people fare poorly when carbs are spared, and not just on cognitive tasks. Many also suffer mild to major anxiety or irritability, especially in the early (induction) stages of the diet. Some folks are just built that way, and may need to increase carb intake slightly while dieting. Others endure the initial stress to reap immediate benefits. Hands down, there is no faster way to lose weight, while improving metabolic health. The degree of discomfort depends largely on the choices you make.
It may take a while for the body to adjust to fat burning. Liver and muscle cells are quite capable of converting certain amino acids (i.e., glutamine, alanine, leucine) to sugar. Also, the body has an enormous supply of energy stored as fat, which can be converted to sugar as well. However, the conversion from fat back to sugar is chemically slow, especially early on. There are also foods and supplements that support this conversion and low-carb diets. Essentially, there is a right way and a wrong way. Most people would benefit from consulting a naturopath, nutritionist or physical trainer while undergoing weight loss.
If you insist on doing it on your own, do it wisely. It's not as simple as eating meat, eggs and cheese. That's the mistaken notion most people have of the Atkins Diet. Over time, Atkins changed his thinking on the ideal low-carb approach. It is a diet in progress. Many other carb-restricted diets have played a part in this evolution, including the Zone, South Beach, and Protein Power plan. Some diets are technically low-carb, while others are more low-glycemic. The latter restricts carb intake to foods that are slowly digested, while also incorporating carb restriction. "Fast" carbs spike insulin and stress the pancreas, which can lead to obesity and diabetes. Sugar and its metabolites are also "sticky". They glom onto and destroy proteins and other biological molecules in blood, which slowly hardens the arteries, impairs circulation and accelerates aging. Carbs, especially refined carbs, are also highly acid-forming in the body, which can eat away at bones if not balanced with alkaline foods. Indeed, sugar and starchy foods are the main culprits behind the epidemic of chronic illness in Western societies.
The best alternative is a high-protein diet. However, there are many issues with animal foods. They can be high in unhealthy fats and toxins, especially if not organic. Those toxins get stored in human fat tissue after ingestion. As the weight drops, toxins are released, which can damage brain cells, making it even more uncomfortable to lose weight. Perhaps some of the cognitive impairment seen with rapid weight loss may be due to nerve damage. Animal foods are also highly acid forming, and could affect bone health. So, make your meat portions small and organic, and fill the rest of the plate with greens. It is best not to add carbs to such a meal, as they do not digest well when combined with high protein foods (except for berries), and the meal becomes doubly acidic. Generally, eat fruit separately from other foods, and choose less sweet or starchy varieties. Also, eat the whole fruit, not juice, which is a concentrated carb. Nevertheless, small amounts of pomegranate, goji, acái or other antioxidant-rich juices or beverages (e.g., tea) are quite acceptable. To improve digestion, drink them about 30 minutes before mealtime to help neutralize free radicals generated from eating a big meal.
Those who need extra carbs should not resort to refined, processed foods. Make moderate allowances for good carbs by choosing berries, apples (with skin), yams (with skin), beans, barley, brown rice and whole grains. Some of these foods are loaded with potassium, which counteracts the acidity of carbohydrate and protein foods. Those on a low-carb diet may eventually want to add a few good carbs back into the diet as well. Sprouted grains and beans are also quite nutritious, especially when eaten raw, so learn how to make your own sprouts. It's quite simple, and can be spiritually uplifting, like growing a garden. Bread made from sprouted whole grains is a super treat. Dip it into hummus made with sprouted chickpeas to increase protein quality. Alternatively, spread almond butter on bread, or make a guacamole dip. Avocados are one of the best choices on the low-carb palette. Eat several daily, if it pleases you.
Reducing carbs to 20 grams per day can be tough on most people, but the weight melts like butter. One of the criticisms of the Tufts study above is that no weight was lost, which puts in question the design or compliance rate for the study. The researchers allowed the women to self-select their diets, to ensure the best possible compliance, but it may be better to lend an expert's touch to such austere diets. It is almost impossible not to lose weight on a low-carb diet, especially one designed to support health, so something was not right with that study.
In the Tufts study, the low-carb dieters had slower reaction times and diminished memory, but they did better than the low calorie control group in attention tests. Previous studies have also shown that low-carb diets can improve attention span. These data beg a few questions, like how is it possible to be more attentive but less capable of remembering? Should a low-carb diet be recommended for people with ADHD? (Note that carbs can incite ADHD in children). Unfortunately, many of these diet studies don't account for many facets of health. More than likely, a nutritionally balanced, low-carb diet would have served to improve both attention and learning.
The Tufts scientists concluded that the brain needs glucose for energy, and diets low in carbohydrates can be detrimental to learning, memory and thinking. However, all low-carb diets are not created equal. A person can't just eat bacon and cheese and expect to fare well, short term or long. A low-carb diet must serve the needs of a person's metabolic type, and must be predicated on the healthiest foods, such as non-starchy veggies, fish, organic animal foods (especially eggs) and selected fruits. There are also vitamin and mineral supplements that support cognitive health when dieting. Nutrients like chromium, magnesium, zinc, alpha-lipoic acid, and fiber help to balance blood sugar. There are even commercial "alkalizers" containing minerals (calcium, magnesium, potassium) that offset the acidity of high protein diets. Black pepper is highly alkaline forming, and also increases absorption of vitamins and minerals, so add it liberally to food.
The trick is to make the right choices. A high protein, leucine-rich diet, combined with moderate carbohydrate restriction (~150 grams daily), was shown to support weight loss, blood sugar metabolism, cardiovascular and cognitive health (Layman and Walker, 2006). During weight loss, muscle mass and bone are easily lost. The amino acid leucine—most abundant in whey protein—prevents muscle loss during dieting. Leucine also helps insulin work more efficiently, helping to preserve muscle mass and transport of glucose into muscles for fuel. On a high-protein diet, weight lost is mostly from fat, not muscle. The reverse is true on a high-carbohydrate diet. High-protein, leucine-rich diets also support HDL (good cholesterol) formation and lower triglycerides, which helps the brain acclimate to fewer calories. Bioactive peptides in whey also help regulate appetite. To support bone health, calcium is important, but must be balanced with magnesium, vitamin D, vitamin K2 and boron, most of which are not readily available in foods. Fortunately, there are several good supplements that support bone, especially on a high-protein diet.
On a high protein diet, carbs must be restricted to induce fat burning. Yet, reducing carbs may also reduce fiber intake, so it pays to sprinkle yogurt, soup or salad with brain-healthy (omega-3) flax meal, and eat plenty of non-starchy veggies, fruits, nuts, seeds and sprouted beans. Also consider a high quality multivitamin, which provides many nutrients that enhance cognitive function, including the B complex, choline, inositol, zinc, iodine, chromium, and antioxidants. Chromium picolinate has been shown to promote serotonin (the feel-good hormone), which may help soften the edge of dieting. Chelated magnesium has also been shown to improve mood.
Not all proteins are created equal, either. While animal or soy protein is acid forming, and potentially bad for bones, whey protein is slightly alkaline, and can help increase bone mineral density. The key again is to balance acidic foods with alkaline veggies and fruits (lemons and limes are highly alkaline forming). Whey protein is ideal, but for vegetarians, hemp seed is another great alkalizing, complete source of protein. Fermented soy protein powder (Jarrow Formulas has a nice product) is also more alkaline and nutritious than conventional soy products. High quality proteins also contain several key amino acids for cognitive functioning. The amino acid tryptophan (with vitamin B6) is necessary for serotonin production, and the amino acids tyrosine and phenylalanine are converted to dopamine, which leads to mental alertness and improved memory. Again, a high-protein, low-carb diet needs to be designed to support healthy metabolism, while not damaging the body, or impairing cognitive performance.
Clearly, people are not all the same metabolically. Some can eat carbs all day and not gain a pound, while others get fat just looking at them. There are many different ways to lose weight, according to your body type. A recent study published in The New England Journal of Medicine showed that a low-fat or Mediterranean diet was almost as effective as a low-carb diet for long-term weight loss (Shai 2008). At first, the low-carb diet provided 20 grams of carbohydrates per day, but was gradually raised to 120 grams over several months. Low-carb subjects were directed to choose vegetarian sources of fat and protein and to avoid trans fats. The authors concluded that it is possible to tailor the diet to accommodate individual preferences. Nevertheless, for most people, low-carb diets will help shed more pounds and optimize blood lipids, especially if other healthy lifestyle changes are employed.
A low-carb regimen changes one from a carb burner to a fat burner. Some types of people freak out during this period, lose their memory, get depressed, nervous or hysterical. But, if you do it right for your metabolic type and stick with it, these difficulties are minor and soon abate. And, if you support it with the right foods and supplements, no one should experience much difficulty.
By the way, it's OK to cheat once in a while. Just reward yourself for living a disciplined life. And, if you do cheat, there are some really tasty, healthy fiber-rich, whole grain breads out there. Look for a low-carb sprouted grain or hemp bread, or pasta, and reward yourself often.
References D'Anci KE, Watts KL, Kanarek RB, Taylor HA. Low-carbohydrate weight-loss diets. Effects on cognition and mood. Appetite 2009;52:96-103.
Layman DK, Walker DA. Potential importance of leucine in treatment of obesity and the metabolic syndrome. J Nutr 2006;136:319-23S.
Shai I, Schwarzfuchs D, Henkin Y, et al. Weight loss with a low-carbohydrate, mediterranean, or low-fat diet. New Engl J Med 2008;359:229-41.
About the author
Dr. Phil Domenico is a nutritional scientist and educator with a research background in biochemistry and microbiology. Formerly an infectious disease scientist, he now works as a consultant for supplement companies and the food industry.