Can a certain protein help the body resist weight gain even though a person continues eating that high-fat diet? A protein could be a key weapon in the battle of the bulge. High levels of GDNF protein could help the body resist weight gain despite high-fat diet. Physiology is the study of how molecules, cells, tissues, and organs function in health and disease.
More than one-third of people in the US are obese. Obesity and its related health problems—including high blood pressure, high cholesterol, diabetes, insulin resistance, and belly fat—affect so many, yet effective treatments are very few. In a new study, "Glial cell line-derived neurotrophic factor protects against high-fat diet-induced obesity," published online March 15, 2014 in the American Journal of Physiology (Gastrointestinal and Liver Physiology).
Simon Musyoka Mwangi and colleagues tested whether higher levels of a certain protein help fight the weight gain and health problems caused by eating the wrong foods, reports the April 1, 2014 news release, " A protein could be a key weapon in the battle of the bulge." Glial cell line-derived neurotrophic factor—or GDNF for short—is a protein integral to keeping the body’s systems in balance (homeostasis) and helping develop and maintain the nerve cells responsible for a host of bodily functions such as digestion and muscle control.
Previous research has shown that elevated levels of GDNF can lead to weight loss in rodents and primates with age-related obesity and prevent weight gain in younger animals
In this study, researchers looked specifically at how the increased presence of GDNF might affect obesity caused by a high fat diet. Researchers compared mice bred to have higher levels of GDNF protein with control mice. The mice were fed either a regular rodent diet (containing ~6% fat) or a high-fat diet (~34% fat).
They found that the GDNF-mice fed a high-fat diet resisted diet-induced weight gain, visceral (around the organs) fat development, fatty liver, high lipid (fat) levels in the blood, and insulin resistance. The GDNF mice also experienced improved insulin sensitivity and increased calorie burn compared to control mice on a high-fat diet.
More research is needed into how GDNF works in the body, but the data presented by Mwangi et al. suggest that it may cause increased calorie burn in both brown and white fat cells and in muscle tissue. Their research also suggests that GDNF and its receptors may be unique and effective targets for obesity prevention and treatment therapies.
The article “Glial cell line-derived neurotrophic factor protects against high-fat diet-induced obesity” is published in the March 2014 issue of the American Journal of Physiology—Gastrointestinal and Liver Physiology. Also, you may wish to check out information about another study, "Abnormal Activation of a Protein May Explain Link Between High Salt Intake & Obesity."
This article is highlighted as one of this month’s “best of the best” from the American Physiological Society’s 10 peer-reviewed journals under the APSselect program. Read all of this month’s selected research articles at the Physiology.org website.
What are the best sources of DHA and EPA or of omega 3 fats?
Most people don't realize that DHA and EPA also are found in green leafy vegetables, in edible algae and microalgae oil, as well as in krill oil, calamari oil, and fish oil.
Some people are searching for vegan sources of omega-3 fats for DHA and EPA because their bodies can't convert ground flax seeds or walnuts into DHA and EPA due to aging or genetic issues. And men are less able to convert flax seeds into DHA and EPA as well as older adults.
Are you getting enough DHA and EPA for your brain and body?
The answer depends upon what your body is able to absorb or convert. Also, your balance of oils depends upon whether you're balancing your oils or are on a low-fat 'reversal' diet or an ethnic diet.
Are you eating the standard American Diet or modernized Northwestern European diet that's heavy on meat and potatoes, sugary sodas, deep fried foods, candy, white flour and table sugar, jam or jelly, salty-fatty foods such as ham and bacon, lots of chicken and few greens, and the usual vegetables and fruits such as iceberg lettuce, a few tomatoes, and maybe some canned vegetables such as green beans or frozen carrots and peas, with perhaps a can of fruit in syrup for dessert or sweetened frozen yogurt and ice cream?
If you are on such a daily diet for years, probably that diet is too low in omega-3 fats and too high in omega-6 fats such as corn oil, cottonseed oil, or canola oil, usually found in salad dressings on the market shelf. Most commercial dressings not in natural food aisles of supermarkets and health food stores usually are not going to be made with expensive cold-pressed oils such as extra virgin olive oil, grape seed oil, sesame seed oil, walnut oil, or rice bran oil.
More likely, they'll be made with the cheaper canola oil, or safflower oil which you find put in commercial salad dressings and even in some brands of store-bought almond milk along with some flax seed oil or safflower oil mixed in to draw your attention to the ingredients label. Most commercial food, that is processed food may contain evaporated can juice, another form of sugar, or fructose, or corn syrup, or agave that's mostly fructose.
Check out the article, Agave Not a Healthy Sugar Alternative After All | Healthy Living. Agave nectar dissolves quickly. It's used as a sweetener. The main polysaccharide in agave nectar is inulin (considered a fiber) or fructosan and is mostly fructose. Usually, it's processed. Also see the sites, Agave Nectar, Is it Healthy? and Sweeteners - sugars: MedlinePlus Medical Encyclopedia.
Alpha linolenic acid (ALA) health benefits
The basic building block of omega 3 fats is ALA, alpha-linolenic acid. ALA also is found in flax seeds, hemp seeds, chia seeds, walnuts, and for those limiting their fat intake, in leafy green vegetables. The standard American diet and standard Western diet eaten in many parts of Europe usually is low in ALA.
Highest concentrations of ALA are found in flax seeds and hemp seeds, that refers to the ground-up seeds, not only the oil extracted from the seeds, processed, and bottled. As far as a recipe, you're better of getting a coffee grinder or nut grinder and grinding up the seeds to a fine powder, then sprinkling on food or putting in blender to puree with other foods or drinking as a smoothie with a mixture of fruits and/or vegetables.
There's more than only omega-3 fats in the seeds. They have phytochemicals, antioxidants, and fibers in the whole seed ground up. Don't let them get rancid. You can store the seeds in your freezer after they're ground into meal. These fats found in nuts and seeds and also green, leafy vegetables are called short-chain omega-3 fats. What they do is act as building blocks of the longer-chain DHA fatty acids needed by the brain, nervous system, and immune system. But don't overdose on them. You need a balance of DHA and EPA and ALA and other phytochemicals. Fish oil, vegetarian algae, and krill oil also have DHA and EPA fats.
Men usually convert less ALA to DHA and EPA than women
The ability to convert grows weaker with aging. So supplements may help. And men convert less ALA to DHA and EPA than women. If you're an older male you might find out whether you need supplements of DHA and EPA or ALA.
The human body can convert short-chain omega-3 fats (ALA) from green leafy vegetables or seeds and certain nuts such as walnuts into EPA and DHA. As you age, this ability to convert may slow down.
Some people at any age still are not able to convert ALA into EPA and DHA from nuts and seeds. The fat in some people who eat lots of nuts and seeds may keep building up where it don't belong -- on the belly. That's genetic with apple-shaped people who gain weight in the abdomen, yet have thin hips, thighs, and sometimes upper arms as well, which also may be due to a combination of aging, changing hormones, and genetic inheritance.
Edible algae, sea vegetables, and microalgae souraces of DHA-EPA omega 3 fats
Food experts are researching Nori sea vegetable as an important source of the omega-3 essential fatty acids EPA and DHA. Also see, Vegetarian DHA Omega-3 - From Algae Oil. No Fish or Gelatin. The DHA in this algae oil is derived from microalgae is grown in a controlled environment, free of contaminants commonly found in fish and fish products, making it ideal for anyone concerned about ocean-borne contaminants such as mercury and other toxins in the ocean and the environmental impact of fish oil supplements.
You could eat fish, but fish may build up mercury is not the only issue. Eating too much animal protein raises IGF-1 levels, which you don't want to do because it may be linked to cancer. For more information on whether raised IGF-1 levels is linked to cancer, check out the medical journal article, "Nutritional Predictors of Insulin-like Growth Factor I and their relationships to cancer in men." Cancer Epidemiology Biomarkers and Prevention 2003; 12: 84-89.
Also see the study or its abstract, "Endocrine disruptors and prostate cancer risk - Adipose tissue concentrations of persistent organic pollutants and the risk of prostate cancer." Journal Occup Environ Med 2006; 48: 700-707. In humans, epidemiologic evidence links specific pesticides, PCBs and inorganic arsenic exposures to elevated prostate cancer risk. Studies in animal models also show augmentation of prostate carcinogenesis with several other environmental estrogenic compounds including cadmium, UV filters and BPA.
Importantly, there appears to be heightened sensitivity of the prostate to these endocrine disruptors during the critical developmental windows including in utero and neonatal time points as well as during puberty. Thus infants and children may be considered a highly susceptible population for ED exposures and increased risk of prostate cancers with aging.
So with eating lots of fish just to get your omega 3 fats, some fish have very little. And increasing fish consumption has been linked to a modest increased risk of prostate cancer and breast cancer in some studies. See the study, "Long-chain omega-3 fatty acids, fish intake, and the risk of type 2 diabetes mellitus." American Journal of Clinical Nutrition 2009; 90: 613-20.
You also may want to look into the edible algae form of omega-3 fats. There's also algae oil. See, Dr. Oz Recommends Fighting Belly Fat with Secrets from the Ocean. Also see the study, “Fucoxanthin-rich seaweed extract suppresses body weight gain and improves lipid metabolism in high-fat-fed C57BL/6J mice” Biotechnology Journal 2010 Sep; 5(9): 961-9; Jeon SM et al. Also check out the study, “Chitosan Supplementation and Fecal Fat Excretion in Men” Obesity Research (2003) 11, 683–688; doi: 10.1038/oby.2003.97; Matthew D. Gades and Judith S. Stern.
Peanuts contain a high amount of omega-6 fats and not enough of omega-3 fats
Shoppers may wonder wonder why almost every general consumer women’s magazine with health articles keeps pushing peanut butter as a polyunsaturated fat instead of coconut milk, which is medium chain triglyceride saturated fat, but not animal fat. Are you loading up on peanut butter only to find that possible excess omega 6 fatty acids are making you feel terrible or worsening some of your blood test results? You need to balance your fatty acids, omega 3, omega 9 and omega 6 fats in a healthy ratio for your body.
Did you know that peanuts contain 4,000 milligrams of omega-6 in each 28 gram, one ounce serving of peanuts, and 1 milligram of omega-3? Check out one of the sources of this information on the link, Dr. Bill Lands, "1 of 4 on Cardiovascular Disease: Omega-6 displaces Omega-3."
Interestingly, today's email from an intelligent, informed reader mentions that very few people, even health experts for that matter, are even aware that the omega-6 fatty acid problem exists. And, with a few notable exceptions, it seems as though most of those aware of the consequences of excessive omega-6 intake do not appreciate the magnitude of the problem. The reader has been studying nutritional issues and controversies for more than three decades.
More recently this reader has been writing letters to journalists, scientists, and politicians encouraging them to learn about added sugars and industrial seed oils, the two components in the modern food supply responsible for many of The Modern Nutritional Diseases.
If omega-6 intake were reduced to preindustrial revolution intake, the November 21, 2010 email received from a reader noted that consumers might suspect there would be a massive decrease in the incidence of chronic inflammatory diseases of all sorts. Moreover, replacing omega-6 with healthy sources of saturated fat in conjunction reduced fructose intake would potentially eradicate chronic inflammatory disease altogether.
An interesting example of a culture consuming minimal omega-6 and fructose is the Kitavans, (See the Kitava Study) the email from the aware reader noted. Eighty percent of the adult population are daily smokers yet there are no strokes and no heart attacks. How could that be? The saturated-fats-are-bad dogma that you may read in a variety of popular media is of particular concern to some consumers perhaps because of the harm caused by demonizing them.
Are saturated fats beneficial if consumed in context of adequate supportive nutrition? Too often solid fats are used in some pleasure or comfort foods. Food surveys employed in epidemology have never obtained sufficient data to distinguish the effects of natural saturated fats from omega-6 trans fats. Yet they are the basis for the current public health recommendation to limit saturated fat intake.
The over-dosing in omega-6 fats issue
Among those who do appreciate the seriousness of the omega-6 problem are Chris Kresser  and Stephen Guyenet . Their articles about omega-6 are about as good as it gets. Also Evelyn Tribole has a website dedicated to the omega-6 problem .
How hazardous to your health is excess omega 6 fatty acids? What can excess omega 6 do to your immune system? Are you eating lots of peanut butter, for example, because you read it might control your blood glucose levels along with cinnamon, but now find you have worsened gum disease from eating excess omega 6? Perhaps you need to balance omega 6 with omega 3 and omega 9 in portions that are best tailored to your own health needs?
You might check out some of the books by John Yudkin, T.L. Cleave, and others about how much or little omega-6 seed oils you need to keep that balance. After all, even olive oil touted as healthy has omega 6 fatty acids. Then ask yourself why cultures consuming lots of fresh pressed, cold pressed, expeller pressed extra virgin olive oil seem to be healthy. What else are they eating to keep their diet in balance? Perhaps lots of omega 3 fatty acids and omega 9 fatty acids?
The edible oils industry must have a lot of commercial, academic, and political clout because there seems to be somewhat of a general, popular consumer magazine media blackout now and then regarding the harmful effects of excessive omega-6 consumption. For example, see, "Case Study: 30-Days of high Omega-6 Diet -- Stiffens Arteries and Increases Belly Fat." As registered dietitian, Evelyn Tribole (M.S. R.D.) notes, " Oprah magazine paid for the study and article but declined to publish the results," according to that article. In that July 25, 2010 article, a daring journalist ate a high omega-6 diet for 30-days (think Super-Size Me), which resulted in stiffer arteries.
In the article, the woman eating a 30-day diet including a specific amount of omega 6 fatty acids didn't have any changes in her weight. But the changes occurred in the fatty acid composition of her bloodstream, body fat, arterial function, and body mass composition, according to that article. Basically, just by increasing omega 6 fatty acids and decreasing omega 3 fatty acid, the changes took place. Check out that article on how too much omega 6 fatty acids increases belly fat and stiffens arteries.
Reduced intake of omega-6s to increase the effectiveness of omega-3s?
Too much omega-3 fats are not healthy either. But check out the online news magazine, Consumer Reports on Health. Did you ever wonder why there's so few mentions of omega 6 fatty acids? Although there are a number of articles about the therapeutic benefits of omega-3s, where's the mention of omega-6? This is strange because as early as 1999 National Institutes of Health scientists were recommending reduced intake of omega-6s to increase the effectiveness of omega-3s.
You need to reduce excess consumption of omega 6 polyunstaturated fatty acids (also called PUFAs). For optimal brain function, omega 3 fatty acids are increased in the diet of children and adults. Did you notice recently that DHA has been added to baby food to increase more omega 3 fatty acids even in the diets of infants of a specific age who are eating their first solid foods?
You don't want to end up with various oils competing with one another for certain enzymes. One type of oil can inhibit the conversion of enzymes. The problem is with the standard Western diet that contains too many dietary plant oils rich in omega 6 PUFAs, such as corn, safflower, and soybean oils. Again, balance is needed. But with all the food you eat in restaurants or fast food eateries and sometimes at home fried in vegetable oils with too high an omega 6 fatty acid content, that's when the imbalance may happen.
What you need to do is check out the article, "Workshop on the Essentiality of and Recommended Dietary Intakes for Omega-6 and Omega-3 Fatty Acids," published in Journal of the American College of Nutrition, Vol. 18, No. 5, 487-489 (1999)
More recently, in a BMJ article, Adherence to Mediterranean diet and risk of developing diabetes: prospective cohort study the authors wrote in the Conclusion, "Our prospective cohort study suggests that substantial protection against diabetes can be obtained with the traditional Mediterranean diet, rich in olive oil, vegetables, fruits, nuts, cereals, legumes, and fish but relatively low in meat and dairy products."
Under the heading Diet and Disease the authors wrote, "Apart from olive oil, adherence to an overall Mediterranean-type food pattern is related to lower plasma concentrations of inflammatory markers and markers of endothelial dysfunction." So, that may be part of the answer to why olive oil is helpful.
The Mediterranean diet does seem to reduce inflammatory markers. To explain why, in a paper, "Dietary Fat Quality and Coronary Heart Disease Prevention: A Unified Theory Based on Evolutionary, Historical, Global, and Modern Perspectives," the authors note that "The only long-term trial that reduced n-6 LA intake to resemble a traditional Mediterranean diet (but still higher than preindustrial LA intake) reduced CHD events and mortality by 70%. Although this does not prove that LA intake has adverse consequences, it clearly indicates that high LA intake is not necessary for profound CHD risk reduction."
So folks, thanks to a reader from the Nutrition Education Project, who sent me this material today, here utilized, with written permission, you also need to investigate the excess omega-6 hazard. Did you ever notice that it is now a century since omega 6 seed oils have been introduced into the Western world's food supply? What were folks using for cooking oil one hundred years ago? The answer is whatever oils or fats were used in anyone's specific ethnic group in the previous century.
Check out the 1895 cookbooks--lots of cream, butter, and/or coconut oil. But you don't want an excess of dairy either. With homogenization, the tiny molecules aren't what you want to load up on. This was not so great 100 years ago for the lactose-intolerant or for those who had adverse reactions to any type of dairy products when bread was buttered instead of dipped in warmed olive oil and garlic as they did along the Adriatic and in some Mediterranean areas. Are you getting enough omega 3 fatty acids in this century as you balance your diet?
A century ago, for example, rendered chicken fat, butter, and cream, were commonly used among Central Europeans, lard among many different peoples in the new World and in many areas of Europe, beef suet/fat among others, coconut oil among people from more tropical areas, and olive oil in Mediterranean regions.
South Asians used sesame oil or clarified butter (ghee). The worse time for shortening in the USA ran from the 1920s to the 1950s when trans fats were sold in cans as solid white shortening. And people started frying potatoes, meats, and fish in transfats, those partially hydrogenated fats. What should you do today? Get enough omega 3 fatty acids and remember, everything in balance.
4. "Multitargeted prevention and therapy of cancer by diallyl trisulfide and related allium vegetable derived organosulfur compounds." Cancer Letters 2008; 269(2): 305-14.
5. "Onion and garlic use and human cancer." American Journal of Clinical Nutrition. 2006; 84(5): 1027-32.