Could how much and often people eat depend on their genes?

Thanks to the Human Genome Project, we humans now know that we are all really very much the same at the level of our DNA. Our genomes are 99.9 percent identical, leaving really only 0.1 percent responsible for giving each of us what we would consider our differences or unique qualities. It's within this 0.1 percent that may also explain why some of us may be more likely to be overweight, obese, or susceptible to a disease such as type 2 diabetes.

One of the most promising developments in nutrition research are the insights provided by studies on how dietary components interact with genes. The knowledge gleaned could one day be used for reducing risk of disease and staying healthier, longer. This area of research is nutritional genomics, or nutrigenomics for short. Eventually understanding more about nutrigenomics could lead to our ability to better personalize our diet plans and make better food choices based on our genetic code.

Interestingly, however, new research suggests that it may be genes themselves that are guiding how much we eat as well as our food choices. The Genetic Subgroup of Look AHEAD and the Look AHEAD Research Group have recently reported findings in the American Journal of Clinical Nutrition that obesity-related gene sequences (loci) may affect how overweight or obese with type 2 diabetes consume food.

New and old tools of science communications

Sci-comm thrives on social media. 

"Writing is thinking on paper" is one of the many beautiful phrases by William Zinsser, author of On Writing Well. Only, if Zinsser had put those words down more than three decades later, he might have added that writing is also thinking on blogs, Twitter, Facebook, and Google+.

As I prepare to head off to San Diego for Experimental Biology (#EB2012)—where I’ll be blogging about The American Society for Nutrition's meeting—I’ve been thinking a good deal about Zinsser’s phrase and about Mary Canady's (@comprendia) call for those attending #EB2012Tweetup to share their new media science communications success stories. My own story begins with me simply blogging and tweeting as a way to think and as a way to remember what it was that I thought. 

No, Dr. Gupta, hummingbird fuel is not "toxic"

Sugar is toxic? Not this hummingbird's opinion.

Whenever someone asks me whether or not sugar or high-fructose corn syrup is "toxic," I remind them that every few days I make up a simple solution of four parts boiled water and one part plain white table sugar. This I use to fill the hummingbird feeders in my yard here in Arizona and the little guys never complain about it.

In fact, they lap up the sweet nectar -- as much as they can get with their long tongues -- to fuel their high metabolism. Then, they fly off (or get chased off) to their perches and I make a note that most will return within 30 to 45 minutes for more. Research shows their little bodies will have oxidized all the ingested sucrose by that time (1).

Walking Off The Influence of "Thrifty Genes"

"I can't help it, it's my genes" is a familiar phrase among frustrated dieters and gym goers who feel they can’t make the scale budge despite all efforts to reduce calories and exercise more. There may be something to their justification. After all, weight can depend partly on genetic makeup (among several other factors).

Luckily, the genetic revolution continues to churn out exciting news giving us hope that, no, we're not completely left at the mercy of the wrong kind of genes. The latest example is a study presented March 14 at the American Heart Association meeting in San Diego. The study found that people could keep their obesity genes under wraps by doing as little as turning off the tube and taking a brisk walk.

Blogging the ASN Meeting at EB 2012

Welcome new followers!

I'm excited to report that I've been selected as official blogger for The American Society for Nutrition (ASN) 76th Scientific Sessions and Annual Meeting in conjunction with Experimental Biology 2012 (EB 2012) on April 21 through 25 in San Diego, Calif.

Click here for a peek at the preliminary program.

What exactly is EB 2012? The conference is a highly anticipated annual event where six scientific societies hold their joint scientific sessions and annual meetings. Besides ASN, other societies represented are: the American Association of Anatomists (AAA), the American Physiological Society (APS), the American Society for Biochemistry and Molecular Biology(ASBMB), the American Society for Investigative Pathology (ASIP), and the American Society for Pharmacology and Experimental Therapeutics (ASPET).

One Tomato at a Time: Feeding the World with Controlled Environment Agriculture

Tomatoes grown with controlled environment agriculture

A simple insalata caprese served to bring about a possible, worldwide agricultural revolution in Tucson, Ariz.

Each tomato in the Capri-style dish was a product of gardening perfection, grown within a precise range of "Goldilocks" (not too hot, not too cold) temperatures with a steady supply of light, carbon dioxide, water, and nutrients. Each bite and burst of fresh-off-the-vine tang only reminds, "Yes, food can and should taste this good."

The lucky few who enjoyed the salad—along with grilled eggplant, squash, fruit, and watermelon juice—were University of Arizona scientists attending the Research and Reports Retreat on Aug. 19 hosted by the Controlled Environment Agriculture Center (CEAC). Nina Fedoroff, professor of biology at Penn State and AAAS president, gave the keynote address.

Can We Prevent a Food Crisis while Preserving Biodiversity?

Nina Fedoroff

To feed a crowded planet and avoid further loss of species, Nina Fedoroff, professor of biology at Penn State University and president of the American Association for the Advancement of Science (AAAS), argues for more focus on biotechnology and controlled environment agriculture. 

"Time is not on our side," she said in a keynote address at a research reports and retreat in Tucson, Ariz., hosted Aug. 19 by The University of Arizona's Controlled Environment Agriculture Center.

Thomas Malthus reasoned in 1798 that exponential population growth would eventually bring on worldwide famine and devastation, but he couldn’t have foreseen the advent of the most sophisticated agricultural production in human history. If he’d had a crystal ball, he would have witnessed plant science take hold—the introduction of post-Mendelian breeding practices, mechanization, intensive propagation and chemical fertilization.

Make getting and giving vaccines a holiday tradition

I'm finally joining the#VaxDrive after being inspired by all the tweets and, especially, from Dr. Rubidium's post. Honestly, I was looking for something just like this to write about, because I've found myself completely disenchanted with this year's holiday season. It has become the season of buying junk for people who don't need it and receiving junk from people who have no idea what to buy for you. It's stressful, it's wasteful, it's expensive, and it's turned into a stupid tradition. Why not just skip it? Instead, save some lives, buy measles vaccines by clicking here. It only costs a dollar to vaccinate each child, or you can vaccinate a village for $500. A whole village!

Another thing: first, go get a flu shot yourself and, second, go help an older person (your mom, dad, grandma, or grandpa) get him or herself a high-dose flu shot. Why a high-dose flu shot? Why not just a standard dose?

Eating Pace and Protein to Control Overeating

One matter that most evidence-based nutritionists and dietitians will agree on is that humans have evolved to be experts in the task of seeking out palatable foods, which generally contain a combination of sugar, fat, and salt. These nutrients, usually scarce over the long span of evolutionary time and highly valued, are what helped lead to the development of our senses.

Nowadays, it is still the sight, aroma, and taste of food powered by sugar-fat-salt reward and satisfaction that still guides our eating decisions, except in a modern environment of widely available food and sedentary lifestyles.

The axe that nutritionists have to grind with food manufacturers is the blatant targeting of our senses with   layer upon layer of bold sugar-fat-salt flavors -- think of potato chips dipped in artichoke dip, French fries and ketchup, pizza topped with pepperoni, and so on. According to David Kessler, these foods are so powerfully appealing to our senses that they may even alter our brain chemistry driving our appetites for more.

Antibiotic resistance: "One of the Greatest Threats to Public Health"

Lance Price

In the United States, there are nine billion food animals produced annually including, 34 million cattle, 108 million hogs, 267 mililon turkeys, and 8.9 billion broilers. In contrast, there is only a human population of about 300 million people. Only a fraction of those people will be treated with antibiotics (for 10 days or so a year), but those nine billion animals will be treated all the time whether they're sick or not.

Combined with overcrowded and unsanitary conditions, feeding healthy animals antibiotics to prevent disease and promote their growth are ideal grounds for evolution of antibiotic-resistant bacteria. These are bacteria that are no longer inhibited or killed by antibiotics at clinically relevant doses and evidence continues to grow that many of these resistant bacteria do eventually make their way to humans (some originated in humans and made their way back).

Egg yolks for eye health

Lutein and zeaxanthin are found in egg yolks.

This morning I spoke with a lady in a coffeeshop who told me she "heard on Dr. Oz" that she should be eating an egg a week for her eyes. I told her differently: she may need to eat them more often than once a week, turn to spinach, or supplement with lutein and zeaxanthin for her aging eyes. Now, because she said she'd get online and read this blog, I want to back my statements up.

In 2009, University of Massachusetts researchers (1) evaluated lutein and zeaxanthin from egg yolks on older adults with low macular pigment optical density, most whom were taking statins to lower cholesterol.* They found that eating four egg yolks per day, and possibly two egg yolks per day, improve macular health after five weeks. Notably, the treatments also increased HDL cholesterol, but not LDL cholesterol.

Omega-3 Overview and Book Review of "Queen of Fats" by Susan Allport

You can’t swing a dead fish these days without hearing about its good fats. The term “omega-3” is now well known throughout the world of nutrition, but this wasn’t always so. Science writer Susan Allport accomplishes the task of chronicling the discovery and rise to stardom of omega-3 oils in The Queen of Fats: Why Omega-3s Were Removed from the Western Diet and What We can Do About Them.

Omega-3s, specifically long-chain omega-3s DHA and EPA found naturally in fish, have overtaken the world of nutrition as one of the most exciting areas of research in the last few decades. They are now recognized as essential for cardiovascular health and guarding against heart disease; DHA for being the most abundant fat in our brains and a key nutrient for infant and brain development as well as long-term brain health in adults; and EPA because it acts to replace other fatty acids in eicosanoid pathways to reduce inflammation in joints and the body overall.

No one would have predicted these facts half a century ago. Back in the 1960s, fats were all considered evil. There was no distinction between what fat was “good” or “bad”, writes Allport. Out of this type of thinking was born the American Heart Association’s low-fat recommendation, which was a recipe for disaster in eating.

Evolution of the "Hero's Journey"

When I was a child, my father told me stories of his time spent working for a gold mining company in the Amazon jungle. He brought home tales of fishing for piranhas, evading giant venomous snakes, and nearly being eaten alive by a swarm of ants. Dad also traded with indigenous tribes. My curiosity was piqued by photos of those natives, so shockingly naked, and their beautifully crafted bows and arrows. Dad had one on display that he had acquired in exchange for a pair of jeans, which my brother and I used to play with until it almost broke (leading to a stern warning).

Dad's stories have stuck with me to this day and I've often reflected on the influence they’ve had on my life. Each story had a some sort of moral in it, although I didn't know it. They’ve guided me in all sorts of situations, be they social, financial or otherwise. Now, as if following wise ancient tradition, he tells these same stories to my children and nephews, his grandchildren.

What chimpanzee predatory behavior can tell us about early human diets

Among primates, we humans are unique in how much meat we eat. On average we eat 10 times as much meat as chimpanzees, who eat the most meat among wild apes. And, unlike any other primate, humans specialize in eating big-game animals (larger than ourselves) like reindeer and mammoths. 

Because of how much meat humans eat, a few major questions are under discussion among biologists and anthropologists: What role did meat play in human evolution? How much meat did human ancestors really eat early on?

Cutmarks on bones, unfortunately, don't say much about whether meat was eaten once a day, once a week, or once a month. But could a few clues into early human diets be gleaned from the extensive field research into the predatory nature of wild chimps?

Living Food Walls for Disadvantaged Youth, Sustainable Communities

The first living wall as it's constructed in South Africa.

My friend Warren Te Brugge has taken on a project that deserves the attention of all who are interested in the ideals of sustainable communities and food security in all parts of the world.

His new foundation My Arms Wide Open® is building the first-ever living food walls with the objective of providing fresh fruits and vegetables to disadvantaged youth in both Vancouver Downtown Eastside and in rural South Africa.

The sister walls will be constructed based on the design of South African artist, Dylan Lewis, who created the exhibition "Untamed" (pictured above) at Kirstenbosch National Botanical Gardens (see more pics of the living plant wall construction here). The exhibition was originally constructed in celebration of the country's hosting of the 2010 World Cup.

The two identical vertical gardens -- one in Vancouver and the second in Cradock, South Africa -- will yield several harvests throughout the year and offer educational opportunities. The main goal: inspire youth to make their own "mini walls" contributing to their health and sustainable communities.

Lindeberg: Focus on Food Choices, Bioactives, not Nutritionism

Dr. Lindeberg weighing a Kitavan man. 

While training in family medicine, Staffan Lindeberg, M.D., Ph.D., read a paper (published in 1985) in the New England Journal of Medicine that would alter the course of his future research. It was entitled "Paleolithic Nutrition" and one of the authors was Boyd Eaton, M.D.

It was about the same time Dr. Lindeberg had heard from a neighbor that humans had the guts of vegetarian -- to which he responded, "Oh yeah?" His neighbor was  influenced by one of a number of nutrition "stories," as Dr. Lindberg calls them, and not based on actual scientific investigation.

"People like John Harvey Kellog [inventor of corn flakes and strong proponent of a vegetarian diet] has had more influence on thinking about a healthy diet than Darwin has," Dr. Lindeberg says.

Intermittent fasting for cardiovascular health

At a time when our ancestors existed as hunter-gatherers in the Paleolithic, it's clear that food was not always available and that the fluctuation of feast and famine was probably more apparent. The theory of thrifty genes has it that our metabolic function is dependent on these fluctuations for optimal insulin function.

So, it's hypothesized that since intermittent fasting may have been instrumental in the selection of our genes, its practice may have lasting benefits on insulin sensitivity. Findings to date in humans are that fasting does improve insulin sensitivity by inducing increases in circulating adiponectin along with changes in plasma leptin. By these mechanisms, intermittent fasting acts on increasing insulin's action differently than physical activity.

Phosphorus and food's future

James Elser, Ph.D.

What can we do about phosphorus and food's future?

The 15th element in the periodic table is not something that comes to mind for most people when they reflect on causes of global food crises of the past. Overpopulation, climate change, crop disease, and soil erosion are more likely to deemed as the instigators of disaster scenarios.

However, phosphorus is essential for every living thing on this planet and, according to estimates, the world's phosphorous -- needed for fertilizing plants -- will peak within half a century.

It turns out there's so much biological demand for phosphorus that it's a limiting factor for life on this planet. The critical nature of phosphorus for the future of crops was well emphasized when Franklin Deleanor Roosevelt was president, but lately government leadership has yet to bring more awareness to the problem of dwindling supplies.

James Elser, Ph.D., hopes that will change.

"That's my dream, that President Obama will say the word 'phosphorus.'" he said, jokingly (or maybe not so much).

Elser, who as a child once wished to become a priest, is on a lifelong journey to save humankind from an entirely different, serious calamity: soaring food prices and widespread world hunger because of phosphorus unavailability.

Can we get any smarter? (A conversation with my boy about neuroscience)

A PET image showing energy consumption in the hungry brain. Credit: Wiki

"Can we get any smarter?" That is the question that piqued the interest of a 14-year-old boy yesterday when he saw it on the cover of the July issue of Scientific American. 

What came next was a reading of Douglas Fox's fascinating "The Limits of Intelligence," some heavy thought in a young teenager's head, and a surprised father who rarely has a conversation with his son about neuroscience.

Plus, that same father is rarely met when he comes home from working all day to a welcome like this, "Hi dad. Do you want to go see a cool movie?"

The movie my boy wanted to see (with me!) was Limitless, a science fiction flick he'd seen before about a man who takes a drug that unlocks his ability to use the "other 80 percent of his brain." We went to see it and, as my son pointed out after the movie, all of what was portrayed was just impossible.

How Diet and Lifestyle Influence Telomere Length

Telomere length has a proportional and linear relationship to omega-3 fatty acids.

With all the attention surrounding telomere length as a biomarker of biological aging, it’s worth pointing out that one nutrient may make a lot of difference: fish-derived omega-3 fatty acids.

The higher the blood levels of fish-derived omega-3 acids in patients with coronary heart disease, the longer the telomeres. This was what was found by researchers recently from University of California, San Francisco.

Omega-3

The study (Farzaneh et al. 2010), published in the January issue of JAMA last year, showed that leukocyte telomere length (LTL) was positively associated with higher blood levels of omega-3 fatty acids (see Figure).

“Omega-3 fatty acids may protect against cellular aging in patients with coronary heart disease,” the authors wrote.

This longitudinal study followed 608 patients with stable coronary artery disease for five years. LTL was measured at baseline and again five years later. The baseline levels of omega-3 fatty acids were then used to compare the rates of telomere attrition over the five-year period.

“Association of omega-3 fatty acids with decelerated telomere attrition may lie in the paradigm of oxidative stress, a powerful driver of telomere shortening,” the authors wrote.

Omega-3 fatty acids have been shown to increase levels of catalase and superoxide dismutase (enzymes that serve important antioxidant roles in the body). The researchers hypothesize that omega-3s may even increase the activity of existing telomerase, the enzyme responsible for the addition of base pairs to DNA during replication.