Every day, we collect the most interesting health and biology news out there, and post it on our Facebook Fan Page and on Twitter. But news and social media move fast, and it’s hard to keep up with everything that comes out every day. Here is a handy roundup of all of the most compelling stories we encountered this week – in case you missed something awesome.
This week, we covered information related to 1) nutrition, 2) sleep & circadian rhythms, 3) physical activity, and 4) aging, fasting & inflammation.
NUTRITION
Cacao
A few weeks ago, we addressed the surprising physical performance benefits of chocolate. We now know that cocoa flavanol consumption does other cool stuff; it even improves skin elasticity and wrinkling.
It doesn’t just make you prettier, though – it also appears to improve endothelial function and Framingham Risk Score – reducing long-term cardiovascular risk.
Polyphenols
Tons of stuff on polyphenols. This week, we learned that consuming berry polyphenols can inhibit post-meal high blood glucose and high blood insulin levels following a carb-rich meal. Similarly, a study published in the journal Diabetes found that a combination of supplemental fruit compounds from red grapes and oranges (trans-resveratrol and hesperetin respectively) lower fasting and post-meal blood sugar levels in obese subjects – with results comparable to the diabetes drug metformin.
In more good news, black tea polyphenols have been shown to suppress fat accumulation and regulate genes associated with fat metabolism. And red raspberries and flavanols derived from the fruit show benefits against a dizzying array of cardiometabolic diseases.
Weight & Metabolism
The basics make a big difference: Eating more minimally processed fruits and veggies is (unsurprisingly) associated with significant reductions in body mass, waist circumference, and fasting insulin.
An 8-week low-calorie diet can restore fasting blood glucose levels to a non-diabetic range for more than half of patients with diabetes – depending on how long they’ve been diagnosed with the disease. 6 weeks of supplementation with the amino acid glutamine also has some modest benefits – improving body composition and lowering fasting blood glucose in people with diabetes.
Breastfed infants have significantly lower levels of appetite-stimulating hormones, like ghrelin, than formula-fed counterparts. This could have long-term implications for metabolism and body mass later in life.
Performance
3 days of beetroot juice supplementation enhances exercise tolerance, enabling subjects to complete more reps of sprint intervals compared to placebo. I’ve tried this product (BeetElite. No affiliation) and felt it improved my performance during high-intensity indoor cycling.
SLEEP & CIRCADIAN RHYTHMS
Administering 1.5 milligrams of melatonin nightly for 2 weeks (a common dose) significantly reduces blood pressure and synchronizes disrupted circadian rhythms in older adults.
We’ve known for a long time that REM sleep is important, but now we have clearer evidence as to at least one of its precise function. Disrupting REM sleep – compared to other sleep phases – has uniquely detrimental effects on memory formation and consolidation.
PHYSICAL ACTIVITY
Exercise prevents the decrease in total energy expenditure that commonly follows major weight loss. This may help stave off the weight regain that seems to befall so many people over time (see the recent Biggest Loser study).
Exercise improves blood flow and oxygen delivery to key areas of the brain that are typically first to succumb to the plaques and tangles characteristic of Alzheimer’s disease. This suggests that exercise may protect against dementia and other neurodegenerative conditions.
From our Facebook page:
And this!
AGING, FASTING & INFLAMMATION
When rodents are given injections of soil bacteria, they experience an adaptive immune response that carries some surprising benefits to the body and mind. The treatment promoted resilience in the face of physical aggression from competitors. It also reduced markers of gut inflammation in a rodent model of inflammatory bowel disease.
Weight loss may have an impact on telomeres – which serve as markers of biological aging. Telomeres protect our genetic information and get shorter with age. Weight loss appears to be associated specifically with telomere lengthening, potentially suggesting a more youthful state. More weight lost corresponds to greater telomere lengthening.
And lastly:
It seems that a lot of the research applied to cocoa analyzes the effects of a specific component of cocoa. Continuing from your previous cocoa post, I would be interested to see the effects (esp. long term) of direct cocoa consumption along with a dose response to develop some practical implications. Dan, would you know how much cocoa would need to be consumed to obtain these levels of flavanols to see such benefits? Paul Jaminet discusses it may be in the range of 50g cocoa/day to obtain about 1g of flavanol/day in his post, “Chocolate, what is the optimal dose?”. And then I wonder if there would be any negative to that level of consistent consumption. Some really interesting information in these links. I was interested in the info on exercise impact on fat tissue, metabolism, etc. Thanks for the great work.
Hi Corey, I agree that would be great to address in greater detail in a future blog, as there is some data out there to form some useful conclusions.
It is a complicated question for a number of reasons.
To keep it brief for now: phenolic content of cocoa differs depending on cultivar, geographic origin, and aspects of the manufacturing process. For example, epicatechin concentration in Costa Rican cocoa may be as high as 16.52mg/g – whereas cocoa grown in Jamaica has been found to be closer to 3mg/g. And other treatments like alkalization interfere with availability of polyphenols. Studies often use standardized extracts of cocoa compounds to control for that variability.
The optimal dose really depends on what physiological effect you are trying to achieve. I’m just speculating here but I would surmise that the dose of flavanol (and type of flavanol for that matter) needed to improve cognition in healthy individuals, for example, may be entirely different than the amount needed for management of neurodegenerative disease. Obviously at a certain level of refinement and concentration, this becomes less of a discussion about food and more of a discussion of drugs.
Thank you very much for another great response. I had not thought about quite a few of the points you brought up.
That is a lot of variability just coming from location alone. The point about desired effect is also a good one, as studies are likely not looking for optimal effect on a healthy individual and in the context of a balanced diet.
I would say the main thing for me would be a desire for practical recommendations for a readily available cocoa product in the context of increased performance in a balanced diet and just to make sure intake is kept within reason.
Thank you again and I really appreciate the thought and information you provided
Thanks for the feedback Corey. I think we can – and will – address that soon 🙂