The Hungry Brain and Energy Density

Part 1 Part 2

One way our ancestor Hominids used to provide their ever hungry and growing brain with calorie-dense and nutrient-dense foods was to become more carnivorous. It worked, but the scientists were bothered with the question: could there be an alternative way?

Harvard University researchers suggested that cooking could play as important a role. It probably happened almost 2 millions years ago. Cooking plant foods made them softer and their "bioavailability" increased. This allowed for saving the cranial space for bigger brains rather that for huge teeth needed before to tear apart raw meets.

Higher energy density made possible energy-costlier activities like hunting. The matter is, the growing areal of grassland caused increase in numbers and diversity of grazing animals. There are signs of this exact behavior in the form of gazelle bones and butcher tools at the hominid campsites of that time.

Researchers consider these signs an important evidence of hominid diet changes toward greater stability and diversity. So they ate better and their brains grew bigger -- creating a positive synergistic feedback in human evolution.

All these facts are seen by scientists as reasons of spreading the Homo erectus from Africa to Georgia (Black Sea,) China, and Indonesia (Java) while Homo habillus and Australopithecus remained in the areas of Chad, Ethiopia, Kenya, Tanzania, and in South Africa. Further inventions such as farming with plant quality improving as well as animal domestication and breading continued the line of improving the quality and stability of human diet.

Where does it leave us now? Yes, human race survived, multiplied, and spread all over the world. However, the energy dynamics established for the species in need of significant energy expenditures remains though this same species (at least the developed part of it) don't need that much energy any longer. Now, we face the dilemma: we can get all nutrients that our big brains need only coupled with too many calories for our dramatically changed life style.

Most fats seem to be protective against Alzheimer disease

In 1989-99, an association was found, between dietary fat composition and cognitive performance in later adult years: the higher intake of monounsaturated and polyunsaturated fats and the lower intake of saturated fat -- the higher cognitive performance. Another, epidemiologic study conducted in 1997 suggested that high intake of total fat, saturated fat, and dietary cholesterol may increase the risk of dementia.

However, researchers at St Luke's Medical Center, Chicago, Ill found increased risk of Alzheimer's disease among people with high intakes of saturated and trans-unsaturated fats and decreased risk with high intakes of polyunsaturated and monounsaturated fats. Consumption of vegetable fat and a high ratio of polyunsaturated to saturated fats were also protective, whereas total fat, animal fat, and dietary cholesterol had no association with Alzheimer disease.

Sources

Brain Res. 1989;505:302-305

Behav Neurosci. 1996;110:451-459

Behav Brain Res. 1999;101:153-161

Am J Epidemiol. 1997;145:33-41.

Arch Neurol. 2003;60:194-200

Why is fat so tasty?

Most animals, including humans, prefer high-fat food to low-fat food. Fatty foods are very palatable though the fatty acids, which make these foods fatty, are tasteless. On the other hand, sweet, sour, salty, or bitter foods are recognized by the corresponding receptors of the taste buds. The receptors then send information to the brain areas responsible for positive or negative sensations called hedonic or aversive. But how the tasteless fatty acids manage to make fatty foods so tasty?

Recently, it was suggested that long-chain fatty acids attaching to their specific transporter in the tongue. These long-chain fatty acids are recognized on the tongue, and then neuropeptides and neurotransmitters such as the famous "reward chemical" beta-endorphin is released in the brain.

Source: J Nutr Sci Vitaminol (Tokyo). 2007 Feb;53(1):1-4.

The ketogenic diet in a pill: "as elusive as ever"

Jong M. Rho and Raman Sankar. Barrow. The ketogenic diet in a pill: Is this possible? Epilepsia Volume 49 Issue s8, Pages 127 - 133 2008

Over the past decade, much progress has been made in
understanding the mechanisms of ketogenic diet (KD) action. From the
complex systemic and metabolic changes induced by the KD have emerged
innovative hypotheses attempting to link biochemical adaptations to its
clinical effects. Despite such developments, the fundamental question
of how the KD works remains as elusive as ever. At present, it is
unclear which of the many potential mechanisms proposed thus far are
directly relevant to the clinical effects of the KD. It is unlikely
that these numerous hypotheses can be unified into a single mechanism
(or a final common pathway). Nevertheless, it may be instructive to
consider each of these putative mechanisms in turn and ask the
following question: if the mechanism or target in question is a
critical determinant of the anticonvulsant efficacy of the KD, then
would a similar intervention known to be based on that mechanism yield
a comparable effect? Perhaps answering this question for each
mechanistic speculation might help substantiate (or invalidate) that
particular hypothesis. Can the KD be packaged into a pill? At present,
the answer is likely “no.” We have yet to discover a “magic bullet”
that completely mirrors the anticonvulsant (and potential
neuroprotective) effects of the KD. However, without a clearer
understanding of the mechanistic elements comprising the complex
metabolic puzzle posed by the KD, we would be left only with empiric
observations, and to wonder curiously how a high-fat diet can exert
such profound clinical effects.

Neurological Institute and St. Joseph’s Hospital and
Medical Center, Phoenix, Arizona, U.S.A. ; and David Geffen School of
Medicine and Mattel Children’s Hospital UCLA, University of California
Los Angeles, California, U.S.A.

Epilepsy Drugs May Treat Alzheimer's

(WebMD) A group of drugs used to treat epilepsy may also treat Alzheimer's and Parkinson's disease.

New research shows treatment with T-type calcium channel blockers, used to treat epilepsy, protected nerve cells from the brains of mice that can be damaged by neurodegenerative disorders such as Alzheimer's and Parkinson's disease.

Researchers say there aren't any effective medications that protect brain cells from age-related damage and degeneration. If these findings hold up under further study in humans, they could lead to a new class of more effective treatments for age-related neurological diseases.

Calcium-signaling pathways play an important role in the survival of nerve cells (neurons) in the brain. As people age, this process can become disrupted and can lead to cognitive and functional decline.

Researchers say that opens up the possibility of using chemicals like calcium channel blockers that are involved in the calcium-signaling process to protect the nerve cells from death.

The study, published in Molecular Neurodegeneration, looked at the effects of treatment with calcium channel blockers on the brain cells of mice.

Researchers found neurons showed an increase in viability after treatment with the calcium channel blockers over both the long term and short term.

"Our data provides implications for the use of this family of anti-epileptic drugs in developing new treatments for neuronal injury, and for the need of further studies of the use of such drugs in age-related neurodegenerative disorders," says researcher Jianxin Bao, PhD, of Washington University in St. Louis, in a news release.

Dietary restriction and life span

A calorie restriction effect on longevity is a very well documented topic of experimental biology. It is important to know that life span researchers deal mostly with small size any meals since their generations change much faster than in larger size animal species. It is also important that only restriction as serious as 30 to 60 percent of "all you can eat" amount can cause significant improvement in health and longevity.

It was first demonstrated in insects, where it yielded up to a 300% increase in life span; then in young small size mammals such as mice and rats, where results were more modest but still impressive. Later the results on adult animals appeared, yet more modest, but still significant. As to the human outcome, published epidemiological studies have reported evidence of reduced mortality rates in persons who have lost weight, regardless of whether the weight loss was due to decreased calorie intake or increased energy expenditure (1). These data are consistent with experimental results where exercise increased average longevity of female rats, despite increased food intake (2).

This consistency is probably the reason for hopes arising from numerous animal data showing benefits of calorie restriction in animals, including improvement in immune status, anti-cancer defense system and decrease in the occurrence of general disease. The hope, if not for increased longevity, is at least for decreased mortality.

Can we use calorie restriction to improve health and to live longer? A daily calorie

restriction of 30 to 60 percent seems to be too hard a sacrifice. Perhaps this is why new hope arose when preliminary information about developing an anti-aging drug mimicking effects of semi-starvation leaked into mass media.

Dr. Masoro from the Department of Physiology and Aging Research, University of Texas, reviewed 54 scientific articles and concluded: "A spectrum of findings indicates that dietary restriction retards the aging processes of mice and rats. It also maintains many physiological processes in a youthful state and, most strikingly, retards or prevents almost all age-associated disease processes." (3) However, it's too soon to use the calorie restriction as a strategy to improve health and prolong life.

"Due to the interrelationships between disease and older age, and the limitations of existing research in this area, most life extension strategies are untested hypotheses. Many strategies merit scientific inquiry, but they cannot be recommended for use. More extensive research is necessary to assess their safety, effectiveness, and socio-economic impact, and to resolve ethical controversies before they can be considered applicable in humans." (Pharmacotherapy, 16(2):183-200, 1996)

More on the topic

Dietary restriction and life span

Can Adults Benefit from Calorie Restriction?

Is calorie restriction stressful?

References

The hungry brain: We humans are what our ancestors ate

Part 1 Part 2

We humans are what our ancestors ate, but... we are strange primates.

Are modern chronic diseases - obesity, hypertension, heart disease and diabetes - the result of modern diets that are so radically different from the diet of prehistoric hunter-gatherers?

At least this is what Doctors Eaton and Konner wrote in their article "Paleolithic Nutrition," published by the New England Journal of Medicine in 1985 and resulted in one of the dieting bestsellers, the "Neanderthin" by Ray Audette. They concluded that the modern chronic diseases - obesity, hypertension, heart disease and diabetes, are the result of modern diets that are so radically different from the diet of prehistoric hunter-gatherers.

Now, however, our knowledge about the evolution of human nutrition has advanced and we know that there was no single, Paleolithic diet but was a much more flexible eating pattern resulted in a "omnivorous" nutrition make up. Studies of modern human populations traditionally living in "prehistoric" environments show that we humans are able to use a wide variety of diets.

It's the energy imbalance that matters

The industrial world, where calorie-packed foods are readily available, now faces diet-related health problems resulting not from deviations from a specific diet but from a lack of energy balance: between the huge energy amounts readily available and the little energy we really need to sustain our comfortable lives. But there's also one less known reason why we are strange primates: the brain's nutrition needs.

The brain of a modern human being is 16 times hungrier than the muscles.
What is extraordinary about our large brain is that every gram of it consumes 16 times as much calories as 1 gram of muscles. AND we use a much greater *part* of our energy budget to feed our hungry brains: up to 25 percent of our energy needs -- compare it with the 10 % in other primates, and 3 to 5 % in other mammals. As a general rule, animals with bigger brains feed on calorie-denser foods, and we humans developed this strategy to the extreme.

Contemporary hunter-gatherers living a prehistorical life style get up to 60 % of their energy from energy-dense animal products. In free-living chimps, it's just 5 to 7%. In the same volume, animal foods bring in more calories than plant foods. What's wrong with this picture is that our eating behavior reflects earlier stages of hominid evolution: we control our eating still judging our meals by their volumes rather than anything else.

The practical part

We can use this fact about our eating behavior, to construct a diet that works for us, and decrease our calorie density. Studies showed that a simple trick like drinking a glass of water before meals help us feel fuller, sooner and on fewer calories. When your grandma told you to eat your soup she was right. Soups, due to the high water content -- vegetable soups, also due to higher fiber content -- result in fewer calories eaten during the entire meal.

When the Hellers (The Carbohydrate Addict's Diet) advised to fight stalled weight loss with a big salad before meals, they were right, for the same reason. The nutrition consequences. It's all good, but there's another aspect of feeding our hungry brain. Not only is it hungrier for calories, it's also hungrier for nutrients than any other organ.

Fat Foods to Soothe Pain and Anger

Fatty meal seems to have comforting and pain-reducing effect.

Research conducted by the Center for Human Nutrition, University of Sheffield, UK, has shown that fatty meal seems to have comforting and pain-reducing effect.

A meal of full-fat pancakes before the pain sensitivity test (a hand immersed in ice-cold water) decreased the sense of pain comparing with low-fat, high-carbohydrate pancakes of equal calorific value.

However, when these people had the same amount of fat, carbohydrates, and calories infused as a liquid meal directly in the stomach through a tube, the pain sensation was not change by any meal.

"From this evidence we think that there must have been a heavy sensory component involved in the study," researchers suggested.

In another study, also from the University of Sheffield, researchers showed that cutting down on dietary fat (from 41% to 25%) caused a higher 'anger-hostility' ratings. Those who continued with a high-fat diet not only kept the 'anger-hostility' ratings unchanged but also felt that their tension and anxiety went down.

The main character in this play may well be cholecystokinin - "CCK." CCK is a gut hormone that is being released in response to fatty food more readily than to any other food. Since CCK inhibits gastric motility, fatty foods slow stomach emptying resulting in a greater 'satiety' or fullness.

Interestingly, CCK is under influence of the "body fat" hormone Leptin (mutations in Leptin gene results in obesity.)

CCK is known for its strong general regulatory properties. These functions were shown to be under CCK control:

Emotionality
Movement activities
Pain sensitivity
Appetite
Thirst
Sexual activity
Curiosity
Learning
Memory

From this standpoint, no wonder that fatty foods improve mood, calm people down, and decrease aggressiveness.

Controlling mood swings with supplements, 15 tips.

Tip 1

Take omega-3. The principal omega-3 fatty acids are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). They may enhance brain activity and alleviate depression. A Finnish study of several thouzand adults found that depressive symptoms were significantly higher among people who don’t eat fish or take omega-3 supplements.

Tip 2

Look for omega-3 ingredient in the groceries. Now you can find them in foods as varied as margarines, eggs from hens fed on flaxseed, even in and tortilla chips.

Tip 3

Hypericum (St. John’s Wort) is a common perennial plant with yellow flowers growing in the meadows and along the roads. It contains many chemical compounds. The active ingredients include hypericin and hyperforin.

St. John's Wort likely lifts mood by boosting serotonin levels, a brain chemical that is a big part of emotion control. Serotonin is "messenger" that affects sleep, appetite, and mood. Low levels of it may result in depression, food cravings and low quality sleep.
Clinical trials found that St. John's Wort controls moderate depression as well as antidepressants do, and with practically no side effects.

In Germany herbal medicines are government-regulated and almost 30 million prescriptions for St. John's Wort are written annually instead of pharmaceutical grade antidepressants.

Tip 4

Recent studies suggest that St. John's wort is of no benefit in treating major depression. Don’t try to substitute your prescription antidepressants before you discuss it with your doctor.

Food/Nutrition and Mood Support


Tip 5

Any restrictive diet can cause depression sometime called diet blues. For people on a low fat diet a quick fix can be a carbohydrate-containing snack – a fruit or a hard candy.
For people on the initial stages of low carbohydrate diets a quick fix is completely different. Turkey and chicken contain a good source of mood-enhancer tryptophan, an amino acid which is a raw material for serotonin - which can be low in people suffering from depression. Poorly eating and sleep habits can negatively influence otherwise normal serotonin levels.

Tip 6

A low-fat diet may be good for your body, but not necessarily for your mind. In a study at Wake Forest University, researchers found that monkeys on a low-fat diet were more hostile than monkeys that were fed foods high in fat. It is though that lower cholesterol decreases levels of serotonin and weakens emotional control.

Low fat diets can make you depressed. Research has linked diets that drastically cut down on all types of fat with an increase in symptoms of depression.

Tip 7

There is plenty of anecdotal evidence that after about one week on a low carbohydrate diet, mood and energy levels go through the roof. Researchers speculate that this can be explained by interplay of brain chemicals after the brain stops running on glucose and switches on ketons for fuel.

The brain is the organ most sensitive to a change in blood glucose level – too little produces fatigue, confusion, irritability and aggression. Decreased glucose sensitivity often develops due to excessive consumption of refined sugar and simple carbohydrates, like in white flour. When the brain adapts to the use of ketones instead glucose, these symptoms disappears.

Study conducted by University of Sheffield, demonstrated that meals rich in fat, significantly reduced pain perception in healthy human subjects.( Physiology & Behavior. 65(4-5):643-8, 1999)

Anti-depressant supplements

Tip 8

Deficiency of vitamin B12 can create disturbances in mood and B12 supplementation helps to normalize the mood. Vitamin B6, vitamin C, Folic Acid (Folate) and Zinc are all essential good mood nutrients. They are needed to make the feel-good brain chemical serotonin from the raw material - amino acid tryptophan. (New England Journal of Medicine 1988;318:1720–8.)

Tip 9

In a clinical trial of healthy young men, consumption of a high-selenium diet was associated with improved mood and decrease of anxiety.
Vitamin D supplementation may be associated with elevations in mood. In a double-blind controlled study, healthy people were given vitamin D3 supplements. Researchers found that D3 supplementation enhanced positive mood and there was some evidence of a reduction in negative mood.

Tip 10

The precursor of serotonin tryptophan is found in many foods, primarily turkey, chicken, fish, cottage cheese, bananas, eggs, nuts, wheat germ, avocados, milk, cheese and legumes and, in lesser amounts, breads, cereals, potatoes and rice. However, these foods also contain competing amino acids tyrosine, phenylalanine, valine, leucine and isoleucine. The solution? Take 5-hydroxytryptophan (5-HTP).

5-HTP is extracted from the seed of the Griffonia simplicifolia plant. L-tryptophan has to be converted to (5-HTP) before it becomes serotonin in the body. In a clinical trial, supplemental 5-HTP had antidepressant effects in bipolar patients. (Acta Psychiatr Scand Suppl 1981;290:191–201.)

Tip 11

Omega-3 Fatty Acids May Reduce the Risk of Depression in Pregnancy. Using British data compiled from pregnant women, the researchers analyzed the association between omega-3 fatty acids and depression. Their findings were supported by an additional analysis, which showed that in countries where omega-3 intake is the highest, the incidence of depression appears to be the lowest. (The Lancet Aug. 1998)
Combining mood-enhancing supplements

Tip 12

S-adenosyl-L-methionine (SAMe) is a supplement naturally formed in the body by an enzymatic reaction. SAMe has been proposed as a treatment major depression (10) and as an agent for improving mood and emotional well-being. SAMe works closely with folic acid and vitamin B-12. (American Journal of Clinical Nutrition, Vol. 76, No. 5, 1158S-1161S, November 2002)

Tip 13

Combined vitamin D and calcium supplementation produced significant elevations in mood. (Journal of Orthomolecular Medicine 1994;9:199–204.)

Tip 14

Studies suggest that vitamin B9 (folate) may be associated with depression more than any other nutrient. Between 15% and 38% of people with depression have low folate levels in their bodies and those with very low levels tend to be the most depressed .
Many healthcare providers recommend a multivitamin that contains folate. If the multivitamin alone is not enough to improve folate function, the provider may suggest adding vitamins B6 and B12 to improve feelings of depression.

Tip 15

The vitamin B12 increases the probability of recovery from major depression and is though to do its best when taken together with other B-vitamins.
The B-complex include: biotin, choline, folic acid, inositol, PABA (para-aminobenzoic acid), and the six "numbered" B vitamins--vitamin B-1 (thiamin), B-2 (riboflavin), B-3 (niacin), B-5 (pantothenic acid), B-6 (pyridoxine), and B-12 (cobalamin). Combination products can simplify the process of taking individual B vitamins for a range of ailments including depression and stress.

Mood Effects of Low-carb Diets

Among those shared with us their weight loss results while on Atkins diet , 347 dieters reported effects beyond weight loss (or its absence):

* Hunger disappearance or appetite decrease - 178
* Diabetes improvement - 169
* Mood improvement, energy level increase - 158
* Absence of cravings - 149
* Physicians approval for the diet - 129
* Joint and muscle improvement - 125
* Headache disappearance - 121
* Exercise improvement - 115
* Muscle gain decrease - 112
* Fungal/yeast infection disappearance - 111
* Heartburn, bloating disappearance - 110
* Thyroid condition improvement - 119

Reported negative results:
* Cravings for high-carb foods increase - 16
* Inability to exercise - 15
* Low-carb foods dissatisfaction - 14

Mood/energy

This particular effect is perhaps the most controversial because it is against the observations, including those conducted in controlled clinical settings, that carbohydrate-rich meals improve mood and energy levels. Apparently, the positive influence reported by the dieters, were due to Atkins diet long-term effects, because during first several days on the diet there were effects consistent with clinical observations on short-term effects of direct intra-gastric infusions of nutrients:

"Hedonic tone was greater and tension lower after the saline and sucrose infusions than after the lipid infusion. From 3 to 3.5 h after ingestion, subjects felt significantly more sleepy after the lipid infusion than they did at these times after the saline infusion, and significantly more dreamy after the lipid infusion than they did after the sucrose infusion. (Physiology & Behavior. 63(4):621-8, 1998)

Another article reporting the influence of nutrients on mood, stress that there were acute and not long term effects:

"Mood improved (a decline in fatigue/dysphoria) following the low-fat/high carb breakfast compared to medium-fat/ medium-carbohydrate or high-fat/low-carbohydrate meals." ("Acute effects on mood and cognitive performance of breakfasts differing in fat and carbohydrate content. "Appetite. 27(2):151-64, 1996)

The short-term positive effects of high-carb meals can be used, for example, for alleviating the PMS syndrome:

"The experimental carbohydrate intervention significantly decreased self-reported depression, anger, confusion, and carbohydrate craving 90-180 minutes after intake. Memory word recognition was also improved significantly." (Obstetrics & Gynecology. 86(4 Pt 1):520-8, 1995)

It is interesting that not all of the clinical studies came to the above conclusion. Study conducted by University of Sheffield, demonstrated that meals, particularly when rich in fat, significantly reduced pain perception in healthy human subjects.( Physiology & Behavior. 65(4-5):643-8, 1999)

Carbohydrate craving obese patients do not improve their mood states through ingestion of a carbohydrate-rich snack. (International Journal of Obesity & Related Metabolic Disorders. 21(10):860-4, 1997)

There were no differences in mood between the groups receiving high-carb drink or water during performance of the military tasks. (Aviation Space & Environmental Medicine. 68(5):384-91, 1997)

The ingestion of sucrose failed to have any substantial effect on mood (Physiology & Behavior. 58(3):421-7, 1995)

"The carbohydrate-supplemented group had a greater total energy intake and carbohydrate intake. No significant differences between carbohydrate were observed in remaining psychological, physiological, or performance-related variables." (International Journal of Sport Nutrition. 5(2):125-35, 1995)

These are rather typical messages:

* I feel great and my energy level has increased. I don't feel sluggish anymore.
* No more mood swings, brain fog, confusion, or depression.
* I feel healthier, more energy (can keep up with the kids, yeah!) and smarter.
* I have a much higher energy level as well as a much more pleasant disposition.
* I have lots of energy and a lot more self esteem.
* I am sleeping like a teenager, and I had sleep apnea before starting the diet.
* I sleep better and I have more energy than my 16 year old daughter
* I'm so infused with energy that I climb the stairs at work without huffing and puffing.
* My energy had increased! Muscle tone had improved even though I wasn't going to the gym.
* When I am eating according to program I feel so much better, sleep better and have more energy
* After the first 3 days the increase in energy was unbelievable, the mental fog and Monday morning blues were gone.
* I have more energy, not so tired anymore, and feel like I'm in control of my appetite.
* I have had a sense of inner peace that I simply can't explain.
* My mood swings have lifted and I'm a much happier person overall.
* I felt better, had more energy, no more brain-fog and I did not feel tired and worn out at the end of the day.