"Cooking is probably the most important thing you can do to improve your diet. What matters most is not any particular nutrient, or even any particular food: it’s the act of cooking itself. People who cook eat a healthier diet without giving it a thought. It’s the collapse of home cooking that led directly to the obesity epidemic."
A recent study analyzed whole kiwifruit and its effects on blood glucose levels. I like reading articles like these because they actually look at the whole food, rather than it’s consecutive parts (e.g. vitamin C or fructose).
The kiwi is roughly 80% dry matter available for carbohdyrate digestion as either fructose, glucose or sucrose. The other 20% consists of dry cells walls and protein, respectively. Interestingly enough, eating a whole kiwi results in the the dietary fiber to swell to four times it orginial digestion, at least in vitro. This study actually shows the benefitcal effects of whole fruit consumption and glucose entry into the blood stream as dietary fiber decreases the rate of diffusion by about 40%, that is, the time it took glucose and fructose to enter from the gut into the bloodstream was reduced by 40%! Cool stuff!
They also note that 100g of kiwifruit, which is just over 1 whole kiwi based on this, equals 5g of glucose (1 teaspoon). However, facts like these overshadow the more important take away from this article: fiber + fructose lows the glycemic response. Most people are worried about the fructose itself and you should if you are drink fruit juices, and smoothies that take away the fiber. These fruit juices are not better for you—don’t consume them.
Eat whole foods!
"Cooking is the great divide between good and bad eating."
"Someone consuming a Nutri-Grain bar in the morning, a Subway Chipotle Chicken and Cheese sandwich for lunch, and a DiGorno pepperoni pizza for dinner, for instance, will have ingested a total of sixty-eight nonfood additives (not including vitamins and minerals) that until recently no human being ate"
Science Round-Up: Omega-6 fats and heart disease, CLA Fights Inflammation and Supplements Do More Harm than Good
Replace Saturated Fat with Vegetable Oils = get Heart Disease.
The battle between what does and does not cause heart disease will continue to ensue. Almost every person in the world has heard that saturated fat causes heart disease. We’ve heard it, told someone else and avoided saturated fat for this reason. But this statement is false and because of only one word: causes. The correct statement should be, “almost every person in the world has heard that saturated fat is associated with heart disease.” Of course there is a difference between cause and association. We cannot come to such a drastic conclusion based on associations. A analogy to help clarify this:
“ice cream is associated with increased risk of drowning.”
There is actually a strong association with an increase in ice cream consumption and death by drowning. Can we come to the conclusion that ice cream causes drowning? No! We do know that when it gets hot outside during the summer months people increase their ice cream consumption and increase their time practicing their backstroke under the sun.
Vegetable oil— it doesn’t even sound right!
Back to my point of saturated fat and heart disease. An association turned causation has lead most people to avoid saturated fat—mainly through animal products and turn towards other fats for “health.” These new “healthy” fats, polyunsaturated fats (PUFA), replaced saturated fats for cooking and food preparation. Put down the butter and use vegetable oils (PUFA) like canola oil, corn and safflower oil for cooking has been suggested for the last few decades. But, these vegetable oils are actually worse than first anticipated. Ramsden et al. recently (Feb 7 2013) publish the “[u]se of dietary linoleic acid for secondary prevention of coronary heart disease and death: evaluation of recovered data from the Syndey Diet Heart and updated meta-analysis.” The investigators looked at 458 men who had recently recovered from a coronary event. One group replaced saturated fat with omega 6 vegetable oils (from linoleic acid) and the other group was given not dietary advice.
What did they find? “[S]ubstiuting dietary linoleic acid in place of saturated fats increased the rates of death from all causes, coronary heart disease and cardiovascular disease.” The authors concluded that linoleic acid did not provide any benefit for preventing a cardiovascular event.
So what is bad saturated fat or vegetable oils? Well, anytime you have an excess of anything in the body it’s a bad thing (too much water). Do I think you should live by the motto “only in moderation?” No. Eliminate these vegetable oils from your diet they contain high amounts of linoleic acid.
Vegetable oils: safflower, poppyseed, grape seed, sunflower, hemp, corn, wheat germ, cottonseed, soybean, walnut, sesame.
Use saturated fats for cooking, especially at higher temperature as they are more stable at these high (>350) temperatures. Keep in mind saturated fats need be in the diet—they maintain brain function and help cell integrity.
Saturated fats for cooking: extra virgin coconut oil, grass-fed butter, clarified butter, ghee, lard, tallow
C.E. Ramsden et al. Use of dietary linoleic acid for secondary prevention of coronary heart disease and death: evaluation of recovered data from the Syndey Diet Heart Study and updated meta-analysis. BMJ. 2013; 346 (feb04 3): e8707 DOI
CLA in Grass-fed Beef & Inflammation
I have asked many of my professors about their opinion of grass-fed meats vs. grain-fed meats. Grass-fed takes the “cake” on being a better opinion mainly because grass-fed beef is lower in fat (and calories), higher in fat-soluble vitamins (vitamin E and A) and also have lower levels of omega-6 fats—the same fats that are responsible for pro-inflammatory eicosanoids.
Another benefit of grass-fed beef comes from the naturally occurring trans-fat conjugated linoleic acid (CLA), which is very different from the trans fats of hydrogenated vegetables oils. CLA has anti-inflammatory properties [1.]
Reynolds et al. (2009) looked at rats that were induced with sepsis—an inflammatory condition resulting in a dysfunctional immune system—through lipolysaccharide (endotoxin). Lipolysaccharide reacts havoc on the immune system by increasing pro-inflammatory cytokines (TNFα, interleukins). What did this study show? Well, high-CLA fed mice had significantly less concentrations of lipopolysaccharides done so by acting through various “downstream” pathways. When I say “downstream” I mean through pathways that act more at the genetic level and how certain genes are expressed (or turned on) can be regulated through environmental factors, like in this case through diet.
The difference between the high-CLA fed mice and low-CLA fed mice was the percent fat composition, 4.3% total fat composition and 0.84%, respectively.
Include meats from grass-fed cattle, and if you tolerate lactose then obtaining cheese, butter are other ways to include CLA in your diet. Keep in mind that the CLA that is sold as a supplement is very different from the CLA you find in beef or cheese, where the former does not offer the same benefits.
Reynolds et al. A conjugated linoleic acid-enriched beef diet attenuates lipolysaccharide-induced inflammation in mice in part through PPARgamma-mediated suppression of toll-like receptor 4. J Nutr. 2009; 139(12):251-7.
Supplements may not be good for your health.
I was walking down the isle at Wal-mart the other day, perusing the aisles looking for some deals while also watching the very interesting people that go to Wal-mart (that’s a different story in itself) when I walked by and saw a sign that read “Diet.” I was not surprised at all to see protein drinks, Slim Fasts, weight loss pills and in the next aisle over a whole section of supplements. Vitamin C, E, A, D, multi-vitamins, every mineral you can not think of, extracts out the wazoo! I got to thinking, “most people when they want to live healthier they turn to supplements.” This couldn’t be further from the truth. Supplements are not healthier, I do not recommend taking them. Why? Well, two recent studies confirm my belief.
Might Want to rethink poppin’ some Vitamin C next time you’re feeling under the weather!
A recent study from Journal of American Medical Association found that Swedish men who took vitamin C supplements (greater than 1000mg) were twice as likely to develop kidney stones compared to those who didn’t supplement with vitamin C. Kidney stones develop usually due to excess calcium or oxalates, and deposit in the ureter leading to some pretty intense pain. Vitamin C is pretty common in the diet I don’t see anyone ever really being deficient in vitamin C.
The second study, also from Journal of American Medical Association, found an association between supplementation of calcium and risk for cardiovascular disease (CVD) Now, increasing calcium intake via supplementation does not mean you will get CVD, your risk for getting CVD only increases—just keep that in mind. This was a pretty large study (n=388,229) and of an older population (ages 50-71) therefore these observations have strong implications especially towards an older population worried about osteopenia and osteoporosis (degrading of bone integrity). Supplemental calcium of more than 1,000mg/day increased CVD death, but this was only found in men not women. Interestingly enough, I decided to do a little more research and found a study by Samelson et al. (2012) who looked at calcium intake and coronary artery calcification—that’s build up of calcium in the blood vessels of your heart (not good). In this observational study there was no significant evidence concluding calcium intake increases coronary artery calcification. The difference between the JAMA and Sameson et al. study? Well, the former looked only at supplementation, while the latter looked at calcium intake (either from food or supplementation). The calcium content of food and that of supplements play very different roles in your body because it’s
What can we learn from these supplemental studies? Taking supplements doesn’t correct for poor food choices, even poor lifestyle choices. Whole foods provide the vitamins, minerals and essential nutrients you need—don’t pop pills! It’s not good for you!
Thomas LD, et al. Ascorbic Acid Supplements and Kideny Stone Incidence Among Men: A Prospective Study. JAMA. Internal Medicine, 2013; DOI: 10.1001/jamainternmed.2013.2296
Xiao Q et al. Dietary and Supplemental Calcium Intake and Cardiovascular Disease Mortality: The National Institute of Health-AARP Diet and Health Study. JAMA Internal Medicine, 2013.
Samelson EJ et al. Calcium intake is not associated with increased coronary artery calcifcation: the Framingham Study. Am J Clin Nutr. 2012; 96(6):1274-80.
"There is simply no other exercise, and
certainly no machine, that produces the level
of central nervous system activity, improved
balance and coordination, skeletal loading and
bone density enhancement, muscular
stimulation and growth, connective tissue
stress and strength, psychological demand and
toughness, and overall systemic conditioning
than the correctly performed full squat"
A large study presented at the American Stroke Association’s International Stroke Conference (say that five times fast) found that a Southern-diet leads to and increase risk of stroke. Increase intake of fried foods (fried chicken, fired fish, fried potatoes) and sugar (sweet tea, pop) are associated with increase risk for stroke.
Fried food = trans fats + added sodium
Sugar foods = glucose + easily digestible calories
The combination of these foods leads to inflammation, elevated insulin levels, increased triglycerides, obesity and a whole list of other things!
Of course it’s from the American Heart Association, who have pretty much come to the conclusion that all we should eat are vegetables and cardboard (“but it lowers your cholesterol!”). Granted I do think fried foods are not the way to go, you can still enjoy Southern-style foods. “But, if you cut out the butter, sugar, and frying then it’s not Southern anymore, is it?”
When scientists are able to make spinach taste like birthday cake, then we’ll be in business.
Fish Oil Doesn’t Fix A Poor Diet
I mentioned this study a few weeks ago in a presentation that I gave on the Whole30. I think it’s really cool because it shows that we can’t just take a “pill” to fix our health problem—whatever that problem my be! So what’s the study? Well, the study was from the British Journal of Nutrition (2013) and they actually fed rats a “Western diet”—a diet that is full of processed foods, high-carbhydrate and high-fat—mainly looking at the intake of omega-6 fats (the same omega-6 fats found in vegetable oils, like canola, sunflower, and peanut). These omega-6 fats elicit a pro-inflammatory response in the body meaning they promote inflammation— something you don’t want! The study actually found that omega-6 fats created unbalance gut bacteria growth leading to inflammation and oxidative stress (i.e. tissue injury). When the rats were given fish oil (loaded with anti-inflammatory omega-3’s EPA/DHA) inflammation in the gut and gut bacteria improved. However, there was a downside! The supplementation of fish oil actually increased oxidative stress. What can we take away from this? Supplementation of fish oil won’t fish your crappy diet—take out take the vegetable oils and other omega-6s will help the problem.
Omega-6 fats in vegetable oils: soybean, peanut, cottonseed, sunflower seed, corn and safflower oil. Even some nuts and seeds, like pumpkin seeds, walnuts, and pine nuts, can have high amounts of omega-6 fats so limit these as they still contain good sources of trance minerals like magnesium and copper.
Fish oil supplementation is still okay, but I recommend you evaluate everything else you are eating first. Are protein levels good? Vegetable intake? Fats? I don’t want to scare you into thinking you shouldn’t take fish oil—but before you keep taking it maybe make changes elsewhere in your diet.
HMB reduces muscle damage and improves recovery
Switching sides now looking at a supplement that has been around for some time. I don’t push supplements that much because I beleive in the power of whole-foods but it’s nice to always look at the research and see what is coming out!
Beta-hydroxy-beta-methylbutyrate or HMB is a natural metabolite for the branched-chain amino acid leucine. HMB is important for cholesterol synthesis, aids in other metabolic functions. It has previously been shown to improve strength and lean mass, and spare muscle protein. In the current study, also out of the British Journal of Nutrition (2013) they had previously trained males consume 3g/day of HMB before completing high-volume of back squats, bench press and deadlifts. They looked at a few markers for muscle breakdown (creatine kinase and 3-methylhistadine), cortisol, testosterone and perceived recovery status (that is how they “felt”).
What did they find? Muscle breakdown was significantly reduced after consuming HMB and perceived recovery was much better. No changes in testosterone and cortisol were observed. I think this study is important because (1) it has not been previously shown that to be effective in trained athletes, (2) I work with a lot of CrossFit athletes who train high-volume and this can have important implications for them during their high-volume days. Now we don’t want to become reliant on supplements like this to continue our work load. Rest days and whole-food diet should still be at the core of the training regimen!
Specific Dietary Fat Helps Eye Sight
I remember as a kid always hearing “eat your carrots, they are good for your eyes.” Then of course you turn into a bunny for the next few minutes downing as many carrots as you can—or maybe that was just me.
Well, it seems as though eating some dietary fat with those carrots or other colorful vegetables and fruits will help those eyes even more. Vegetables like carrots, bell peppers, tomatoes and sweet potatoes contain two important carotenoids used in vision: lutein and zeaxanthin. For these carotenoids to be absorbed they need some type of fat around. In another study from the Britsih Journal of Nutrition (2013)—I am not British by the way—they looked at the bioavailablity of lutein and zeananthin in the presence of different dietary fats. Bioavailablity really just means how well something is absorbed (low bioavailablity means it’s not absorbed by your gut very well).
“Results showed that lutein and zeaxanthin bioaccessibility was greater (about 20–30 %, P < 0·05) with butter and palm oil [saturated fats] than with olive and fish oils.” It seems as though some natural compounds in the oils affected the uptake of lutein and zeaxanthin. “Oral administration of rats with spinach and butter over 3 d led to a higher fasting plasma lutein concentration than oral administration with olive or fish oils.” Therefore, this shows that saturated fats (e.g. butter, palm oil, coconut oil) are better for the absorption of carotenoids in vegetables and fruits compared to other fats, like monounsaturated fats (e.g. olive oil, almonds) and polyunsaturated fats (e.g. marine oils). (The difference here was in the fact that saturated fats created micelles that are smaller compared to the unsaturated fats making the carotenoids more accessible to gut absorption).
Now, don’t go out and down a stick of butter every time you eat just make sure that when you cook your food you include small amounts (I tell people thumb-sized portions) of saturated fats. This also has implications into people who eat raw food—they might get the benefits they need if they start cooking!
Sanjoy Ghosh, Erin Molcan, Daniella DeCoffe, Chaunbin Dai and Deanna L. Gibson. Diets rich in n-6 PUFA induce intestinal microbial dysbiosis in aged mice. British Journal of Nutrition, available on CJO2013.
Jacob M. Wilson, Ryan P. Lowery, Jordan M. Joy, Joe A. Walters, Shawn M. Baier, John C. Fuller, Jr, Jeffrey R. Stout, Layne E. Norton, Eric M. Sikorski, Stephanie M. C. Wilson, Nevine M. Duncan, Nelo E. Zanchi and John Rathmacher. β-Hydroxy-β-methylbutyrate free acid reduces markers of exercise-induced muscle damage and improves recovery in resistance-trained men. British Journal of Nutrition, available on CJO2013.
Béatrice Gleize, Franck Tourniaire, Laurence Depezay, Romain Bott, Marion Nowicki, Lionel Albino, Denis Lairon, Emmanuelle Kesse-Guyot, Pilar Galan, Serge Hercberg and Patrick Borel. Effect of type of TAG fatty acids on lutein and zeaxanthin bioavailability. British Journal of Nutrition, available on CJO2012.
Whole Egg consumption + Low-carbohydrate diet improves lipid profiles and insulin sensitivity in individuals Metabolic Syndrome.
I know I push egg yolks alot, but too many people still freak out about the whole “cholesterol” thing—it’s old science people! A recent study out of Metabolism (2012) looked at individuals with Metabolic Syndrome (obese, hypertensive, dylipidemic, elevated fasting glucose) who were put on a low-carbohydrate (25-30% of energy from carbs) diet and either asked to consume 3 whole days per day or the equivalent amount of yolk-free substitute for 12-weeks.
A serving of the whole-eggs: 534 mg cholesterol, 0g carbs, 16g protein, 12g of fat.
A serving of the yolk-free substitute:0 mg cholesterol, 2g carbs, 14g protein, 0 g of fat.
What did the find? The combination of carb restriction and whole egg consumption resulted in weight loss and improvements in blood lipids. Most notably “all participants had reductions in VLDL particle size, atherogenic lipoprotein subclasses (small LDL, large VLDL, IDL), and oxLDL.” OxLDL are those associated with infiltration of blood vessel walls leading to atherosclerosis and heart disease. This kind of shows again that a low-carbohydrate diet can improve your blood lipids, especially the blood lipid particles that greatly influence heart disease risk. But it also shows that consuming a whole-egg can have positive outcomes on cholesterol and triglyceride metabolism. It shows that increased consumption of dietary cholesterol (from whole eggs) does not lead to heart disease risk—opposite of what many people believe—or at least in the presence of a low-carbohydrate diet! Now, don’t go out and eat a dozen eggs like some meat-head trying to impress the ladies just don’t toss the egg-yolk out when you scramble up eggs in the morning.
Gut Issues from eating Beans and Wheat—due to plant lectins
Let’s get to the “gut” of the issue. You probably have a messed up intestinal tract—and it’s probably due to a few things: unbalanced gut bacteria, environmental toxins, or even what you eat. I am going to point my finger at beans and wheat here. Beans (legumes) and wheat (cereal grains) contain potentially harmful substances called lectins. Lectins in plants function to improve the survival of these plants (mainly their seeds) because, unlike animals, plants can’t get up and run away (derp!)—so they need some type of “defense mechanism” to increase their survival. Lectins in the diet come from grains and legumes. A study from Gut (2000), kind of old I know, feed rats two dietary lectins (Phaseolus vulgaris lectin (PHA) from kidney beans, and wheat germ agglutinin (WGA)) and looked at changes in the stress response of these gut cells. These gut cells have special molecules called heat shock proteins (HSP), which respond to stress or environmental conditions, like infection or inflammation. HSP are like little housekeepers inside your cells that make sure everything is clean and working properly. It’s like having a babysitter around with the kids—the HSP make sure the house doesn’t get destroyed!
What did the study find? Well, when the gut cells were exposed to these lectins their HSP decreased dramatically, meaning their stress response was lowered. In other words, the housekeeper job of HSP was impaired and the kids were allowed to run wild! The house burned to the ground! We want our HSP to be in working order, especially in our gut because our gut is the first line of defense against a lot of harmful substances we consume in our food! Another reason to eat a Paleo diet? I think so!
Blesso CN et al. “Whole egg consumption improves lipoprotein profiles and insulin sensitivity to a greater extent than yolk-free egg substitute in individuals with metabolic syndrome.” Metabolism. 2012 pii: S0026-0495(12)00318-6. doi: 10.1016/j.metabol.2012.08.014.
Ovelgonne JH et al. “Decreased levels of heat shock proteins in gut epithelial cells after exposure to plant lectins.” Gut. 2000; 46:679-687.
If you are interested in leaning out, managing those food cravings or just want to experiment with intermittent fasting (IF) then I suggest you check out the link above. Dr. Berardi has very extensive review and personal experience with IF that will answer any questions and hopefully get you started!
Video by Dr. Yoni Freedhoff, a Family Practice doctor and Assistant Professor in Ottawa. Here is his blog: Weighty Matters
This video is on the food industry—very interesting. Personally, I would have to agree with much of what Dr. Freedhoff says, especially when it comes to kid’s nutrition. Avoid the processed foods—in fact don’t even walk down the aisles at the g-store! It’s a trap!
Minding Your Mitochondria by Dr. Terry Wahls
A great talk about MS and the ability to cure (or at least slow) the process of disease through diet—functional foods!