 Welcome to the Nutrition Facts Podcast. I'm your host, Dr. Michael Greger. The coronavirus pandemic has made many of us very aware of the importance of maintaining and improving our health. Make that your silver lining. Because the more positive change we can make to our diet and lifestyle, the better. It's time for the Nutrition Facts Grab Bag, where we look at the latest science on a whole variety of topics. Next up is a new story on the role of epigenetics in the obesity debate. Identical twins don't just share DNA, they also share the uterus. Might that also help account for some of their metabolic similarities? Fetal overnutrition, evidenced by an abnormally large birth weight, seems to be a strong predictor of obesity in childhood and later in life. Could it be you are what your mom ate? A dramatic illustration from the animal world is the crossbreeding of shetland ponies with massive draft horses. I mean, either way, the offspring are half pony, half horse, but in the pony uterus they come out much smaller. Thank heavens for the poor pony. This is presumably the same reason why the mule, donkey dad and mare, is larger than the henny, stallion and donkey mom. The way you test this in people is to decide the size of babies from surrogate mothers after in vitro fertilization. Who do you think most determines the birth weight of a test tube baby, the donor mom who provided all the DNA, or the surrogate mom who provided the intrauterine environment? When it was put to the test, the womb won. Incredibly, a baby born to an obese surrogate mother with a skinny biological mom may harbor a greater risk of becoming obese than a baby from a big biological mom born to a slim surrogate. The researchers conclude the environment provided by the mother is more important than her genetic contribution to birth weight. The most compelling data comes from comparing obesity rates in siblings born to the exact same mother before and after her bariatric surgery. Compared to their brothers and sisters born before the surgery, those born when mom weighed about 100 pounds less had lower rates of inflammation, metabolic derangements, and most critically three times less risk of developing severe obesity, afflicting 35% of those born before the weight loss compared to 11% born after. The researchers conclude these data emphasize how critical it is to prevent obesity and treat it effectively to prevent further transmission to future generations. But wait, mom had the same DNA before and after surgery. She passed the same genes down. How could her weight during pregnancy affect the weight destiny of her children any differently? Darwin himself admitted that the greatest error he committed had been not allowing sufficient weight to the direct action of the environment like food independently of natural selection. We finally figured out the mechanism by which this can happen, epigenetics. Epigenetics literally meaning above genetics layers an extra level of information on top of the DNA sequence that can be both affected by our surrounds and potentially passed on to our children. This is thought to explain the developmental programming that can occur in the womb depending on the weight of the mother or even your grandmother. Since all the eggs in your infant daughter's ovaries are already preformed before birth, a mother's weight status during pregnancy could potentially affect the obesity risk of her grandchildren too. Either way, you can imagine how this could result in an intergenerational vicious cycle where obesity begets obesity. Is there anything we can do about it? Well, breast-fed infants may be at lower risk for later obesity, though the benefits may be confined to exclusive breastfeeding as the effect may be due to growth factors triggered by exposure to the excess protein in baby formula. The breastfeeding data is controversial, though, with charges leveled of a white hat bias. That's the concern that public health researchers might disproportionately shelve research results that doesn't fit into some goal for the greater good, in this case preferably publishing breastfeeding studies showing more positive results. But of course that's coming from someone who works for an infant formula company. Breast is best regardless. Its role in the childhood obesity epidemic just remains arguably uncertain. Prevention may be the key. Given the epigenetic influence of maternal weight during pregnancy, a symposium of experts on pediatric nutrition concluded that planning of pregnancy, including prior optimization of maternal weight and metabolic condition, offers a safe means to initiate the prevention rather than treatment of pediatric obesity. Researchers said than done, but overweight moms to be may take comfort in the fact that after the weight loss in the surgery study, even the moms who gave birth to kids with three times lower risk were still, on average, obese themselves, suggesting weight loss before pregnancy is not an all or nothing proposition. Next up, we look at how the nutrition and health effects of quinoa compare to whole grains. Approximately 90% of the world's calories are provided by less than 1% of the quarter million known edible plants. The big three are wheat, corn, and rice, the reliance upon which may be unsustainable given the ongoing climate crisis. This has spurred new interest in to underutilize crops like quinoa, which might do better with the drought and heat. Quinoa has only been introduced in the Northern Hemisphere recently, but humans have been eating quinoa for more than 7,000 years. I mean, is there any truth to the superfood designation, or is it all just marketing hooey? Quinoa is a pseudo grain, since the plant it comes from isn't a type of grass. Technically, it's a seed-like fruit. It does have a lot of protein, also lots of vitamins and minerals, but so do all whole grains. Yeah, it has more protein than other grains, but since when do we need more protein? Fiber is what we're sorely lacking, and its fiber content is relatively modest, compared to barley or rye. Pretty strong on folate and vitamin E, and leads the pack on magnesium, iron, and zinc, so nutritious, I'm sure. But when I think superfood, I think some sort of special clinical benefit. So, you know, broccoli is a superfood. Strawberries are a superfood. Garlic is a superfood. But what about quinoa? Consumer demand is up, thanks, apart to perceived health benefits. And lab animals has all sorts of purported benefits, but there have been very few human studies. The first trial was before and after study of like quinoa granola bars that showed drops in triglycerides and cholesterol, but with no control group. You don't know how much that would have happened without the quinoa. About a cup a day of quinoa for 12 weeks led to a 36% drop in triglycerides. I mean, that's comparable to what one gets, you know, with triglyceride lowering drugs or high-dose fish oil supplements, which is better. Regular quinoa or red quinoa. Well, red does have about twice the antioxidant power, leading the investigators to include that red quinoa might significantly contribute to the management and or prevention of degenerative diseases associated with free radical damage, though it's never been put to the test. What about black quinoa? Both red and black are equally antioxidant rich, both beating out the more conventional white. The only caveat I can find is to inform your doctor before you're next colonoscopy. Else they might mistake it for parasites. Colonoscopy revealed numerous egg-like, tan yellow ovoid objects of unclear cause, but it was just undigested quinoa. Finally today, the health benefits of spending time in nature. For perhaps 99.99% of our time on Earth as a species, we've been living outdoors in the natural environment. Might there be a health benefit turning now and again and surrounding ourselves with nature? That's a question urban planners have asked. Are people living in greener areas healthier than people living in less green areas? Should we put in a park or another car park? In a greener environment, people report fewer symptoms of illness and a better perceived general and mental health and a considerable amount. Assuming the link is cause and effect, 10% more green space leads to a decrease in the number of symptoms that is comparable with a decrease in age by five years, but that is a big assumption. I mean, still you could imagine some potential mechanisms why it could be. I mean, it could mean less air pollution and air pollution is no joke. It's the fifth leading cause of death on planet Earth, wiping out about 5 million people a year. Of course, our diet kills twice as many as killer risk factor number one. So it could be an anti-pollution effect, or maybe there's something special about experiencing green spaces beyond them just offering more opportunities to exercise. And that's probably the simplest explanation, natural settings, simply promote health-enhancing behavior rather than having specific and direct benefits for health. I mean, it's harder to go jogging in the park when there is no park. Ironically, it seems that even when people have access to nature, they don't necessarily take advantage of it. And even if there was a link, instead of natural environments drawing out increased physical activity, maybe physically active individuals are just drawn to living where there's nature. But what I wanted to know is, apart from the promotion of physical activity, are there added benefits to health of mere exposure to national environments? Now, certainly just exposure to sunlight can treat things like seasonal affective disorder and provide the sunshine vitamin, vitamin D. But are there other inherent benefits? You don't know until you put it to the test. Some of the studies are just silly, though. At first, I thought this was about academic achievement and vegetarianism, but no, vegetation. They found a correlation between non-forest vegetation and graduation rates for schools. Maybe the Ivy League edge is all just cause the Ivy? The view through a window may influence recovery from surgery. This suburban hospital, some patient rooms looked out at trees and others just to a brick wall. And the surgical patients assigned to rooms with windows looking out on a natural scene had shorter post-operative hospitals. Stays and took fewer potent painkillers than similar patients in similar rooms, but with windows facing a brick wall. You can't chalk that up to a vitamin D effect. What could it be about just looking at trees? Maybe it's the vitamin G, just the color of green. We know how healthy it is to eat our greens. What about just looking at them? Researchers have people exercise while watching a video simulating going through a natural color green setting the same video in black and white or everything flipped to red. And no differences were noted, with the exception of the red just making people feel angry. The most interesting suggested mechanism I ran across was fractals. You know how the branches of a tree kind of have the same shape of a tree themselves? Fractal patterns are found throughout nature. You can see a cascade of self-similar patterns over a range of magnifications. And hook people up to an EEG, and for some reason our brain apparently seems to like them. Regardless of the mechanism, if you compile together all the controlled studies and using nature as a health promotion intervention, you tend to see mostly psychological benefits, whereas the findings related to physical outcomes were less consistent. The most common type of study outcome was self-reported measures of different emotions, like what makes you feel better staring at a kiwi fruit orchard, or staring at a building. Awkwardly described, thanks presumably to the language barrier as a comparison of synthetic versus organic stimulation. Natural settings may make people more attentive, less sad, and when it comes to some objective measures, like blood pressure, no significant effect. So you ask people who exercise outdoors, and they say they feel great, suggesting that green exercise activities have the capacity to increase mood, focus, and energy, and within just like five minutes of being out there in the woods. Yet these studies tended not to be randomized trials. They just asked people who already sought out nature what they thought about nature, and so no wonder they like it, otherwise they wouldn't be out there. But hey, nature-based interventions are low cost, often free, in fact, and non-invasive, unless you count the mosquitoes. So if you want a natural high, I say go for it. Whatever makes you happy. Though evidently not all green exercisers like trees, golfers just viewed them as obstacles. We would love it if you could share with us your stories about reinventing your health through evidence-based nutrition. Go to nutritionfacts.org slash testimonials. We may share it on our social media to help inspire others. To see any graphs, charts, graphics, images, or studies mentioned here, please go to the Nutrition Facts podcast landing page. There you'll find all the detailed information you need, plus links to all the sources we cite for each of these topics. For a vital timely text on the pathogens that cause pandemics, you can order the e-book, audio book, or now hard copy of my latest book, How to Survive a Pandemic. For recipes, pre-order my How Not to Diet Cookbook out this December. It's beautifully designed with more than 100 recipes for delicious and nutritious meals. And all proceeds I receive from the sales of my books go to charity. NutritionFacts.org is a non-profit, science-based public service where you can sign up for free daily updates and the latest in nutrition research via bite-sized videos and articles. Everything on the website is free. There's no ads, no corporate sponsorship. It's strictly non-commercial, not sign anything. I just put it up as a public service. A labor of love as a tribute to my grandmother, whose own life was saved with evidence-based nutrition.