The Science of Dulse
First Publish on Health & Nature News
What is Dulse?
Dulse, often referred to as Rhodymenia or Palmaria palmata, is a red alga of the Rhodophyta division that makes its home primarily along the Pacific and Atlantic coasts1. There are many variations of this particular alga which gives Dulse its unique variety of flavors when used for culinary purposes, and its blend of nutrients when considered for its health benefits. It is extremely similar to seaweed – often referred to as seaweed, however Dulse contains more fiber and protein than normal seaweed. This “wonder plant” has been used for its culinary and medicinal benefits for centuries in many different parts of the world.
Health Benefits of Dulse
Although critically-acclaimed for thousands of years through tribal knowledge for its ability to supplement flavor and texture in food, Dulse also carries a profound list of different health benefits to humans due to the vast array of phytonutrients it contains. The list of different minerals and trace elements it contains goes well beyond that of most vegetables. Further, Dulse is definitely not lacking in flavor. One would think that a phyto food so rich in bitter nutrients would lack in menu popularity, however, of all the marine algae, Palmaria palmata seems to have a flavor more favorable to the demands of the western palate. From lowering blood pressure to priming the immune system, Dulse has proven itself time and time again to be a top contender in the battle of the super foods.
Besides being an excellent food additive, Dulse has shown great potential for reducing blood pressure by multiple routes. One study demonstrated the potential of P. palmata protein hydrolysates (proteins that have been fractionalized) acting as multifunctional food ingredients for the prevention/control of hypertension2. Dulse seems to have the unique ability to do this by containing protein fractions that inhibit the activity of Angiotensin Converting Enzyme (ACE) and dipeptidyl peptidase (DPP) IV3. These pesky little enzymes are directly responsible for causing vasoconstriction in blood vessels and thus play a role in elevated blood pressure. Potassium is a mineral that plays a vital role in blood and tissue osmolality and blood pressure, in which Dulse has been proven to be abundant in7. Simply varying dietary potassium intake (mainly in favor of potassium) in humans can result in remarkably beneficial effects on blood pressure and cardiovascular disease endpoints4.
Good source of amino acids
Amino acids are the building blocks that make up the majority of the human body. Proteins, whether structural or functional, are made up of these building blocks and are critical to human life. Amino acids attach to one another in a particular geometric fashion to form thousands of uniquely shaped proteins that serve a given function. So, from neurotransmission to chaperoning other molecules, amino acids play one of the most crucial roles in sustaining life in the majority of the animal kingdom. Dulse has also been shown to contain above normal amounts of protein when compared to other plants5. In addition to being excellent sources of protein and essential amino acids, Dulce also contains relatively large amounts of minerals, vitamin C and vitamin B12 when digested and analyzed6. Reviews of the chemical constituents of Dulse have also shown the amounts of electrolytes, vitamins, minerals, and sterols it contains7 and the benefits of them. With all of the qualitative and quantitative evidence in Dulse’s favor, it has definitely proven itself to be a valuable source of macronutrients both for the vegetarian and non-vegetarian diet.
Omega 3 fatty acids are long-chained, polyunsaturated carboxylic acids that contain double bonds at positions that no enzyme in the human body can create – namely after the 9th position to alpha carboxylic acid end. The term omega 3 simply means that the fatty acid contains a double bond between the 3rd and 4th carbon to the methyl terminus. All that to be said, omega 3 fatty acids are not manufactured by humans but are absolutely critical to our survival. From helping to reduce inflammation to improving memory, these unique little unsaturated alkanes have proven themselves to play quite the role in human health. It has been revealed that when Dulse is digested and analyzed, there are some pretty amazing lipids that it’s got in its warehouse. Polyunsaturated fatty acids such as eicosapentaenoic acid (EPA) and key phospholipids have been found in Dulse extracts8, which in turn help prevent inflammation and tissue oxidation via lipopolysaccharide-induced nitric oxide production9. This just means that the polar and non-polar fatty acids found in Dulse come in and stop some of our favorite tissues from being flooded and damaged in the presence of certain pathogens. The omega-3s found in Dulse are in fact the good fats… not the bad ones. So, eat your good fat – eat Dulse!
Oxidation is the process in which an unstable atom, or a molecule that contains an unstable atom, swipes an electron from another atom to fill its outermost valence shell in order to satisfy the Octet Rule. Simply stated, an unruly, reactive chemical that destroys anything it touches. We call these little trouble makers radicals. Reactive oxygen and nitrogen species (radicals) are generated by our bodies by exposure to different physiochemical conditions, various endogenous systems, or pathological states causing oxidative stress. This, of course, does not include the plethora of different exogeneous radicals formed in our atmosphere. There is ample evidence that supports Dulse’s proud ownership of different antioxidants to help prevent against oxidative damage10,12. Antioxidants such as ascorbic acid, gallic acid, and a variety of polyphenols found in extracts of Dulse12 are what give it its one-two punch to fight off radicals that cause oxidative damage.
Along with its other medicinal benefits, Dulse has also been shown to reduce inflammation in mammals. Inflammation can be initiated by several factors in humans, one of them being the release of biochemicals (chemokines) from a target tissue in the hopes of increasing circulation and tissue flooding to the area. This can often be extremely painful. These Chemokines represent secreted proteins that are rapidly induced in response to various inflammatory and mitogenic stimuli, and not expressed in resting cells. These proteins are implicated as major participants in acute as well as chronic inflammatory reactions, inhibition of hematopoiesis, modulation of angiogenesis, and fibroplasia13. Extracts of Dulse contain phytonutrients that can reduce the amounts of some of these biochemicals, such as tumor necrosis factor-α, interleukin 6, and nitric oxide14 just to name a few.
The first line of defense for our immune system is our gastrointestinal tract. Maintaining a clean gut and keeping it populated with the right kinds of bacteria is paramount to human health. The microbes within the lower GI tract perform quite a variety of functions important for normal physiology, including promoting maturation of the immune system15 and development of the GI tract16. Dulse fortunately plays an important role in this. Xylans are fibers that have been shown to play a vital role in human gut health17. They do so by preferentially stimulating the growth of prebiotic Bifidobacterium and other lactic acid bacteria in the gastro-intestinal tract18. Dulse, fortunately, has been shown to be replete in this unique oligosaccharide19. Friendly flora takes up these fibers and uses them as prebiotics, allowing them to multiply and use as an energy source. Undegraded xylans act as soluble dietary fiber, cleaning out the gut as they make their way down the GI tract via normal peristaltic movement.
So now we see why Dulse is one of the forerunners for 1st prize in the race for the King of the Super Foods. Nature has seemed to definitely provide a delicious alternative to some of the most well-known prescription medications for treating certain health conditions. From blocking the molecules that cause inflammation, to providing the food source for some of our favorite friendly flora, Dulse has continued to gain popularity in the field of holistic medicine. Further, although Dulse has been used medicinally for centuries, scientists still continue to uncover more and more benefits from this amazing sea plant.
Chad Brey, a California State University, Northridge alumnus, has since worked as a chemist for various analytical and research facilities such as Amgen, Baxter, and Nusil Technology. Since 1997 he has worked in the dietary supplement industry for companies such as Earthwise Nutrition (formerly known as Great Earth Vitamins) and has earned a number of certificates as an IACET-certified dietary supplement specialist. Chad has written dozens of technical articles on the specifics of how certain dietary supplements work. Chad has formulated and developed small and large molecules in research and development laboratories since 2003 and continues to consult others in R&D today.
Read more blogs from Chad Brey
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