***This is a research paper that I wrote while in school. Just another reason why Flaxseed is so beneficial:)
Flaxseed hit the market just a few years ago as a beneficial food, and people worldwide embraced it. Today, supplemental products for flaxseed are everywhere. Recent literature tells us that this little seed, whether in whole food or compressed oil form will provide us with optimal health. One of the newest claims is that Flaxseed can benefit cardiovascular health by reducing the risk of atherosclerosis and heart disease.
The purpose of this research essay is to investigate whether and under which conditions dietary flaxseed (linseed, Linum usitatissimim) can provide necessary benefits to Cardiovascular Health. In section 1 of this paper, I provide definitions of Cardiovascular Disease, Atherosclerosis as well as give a brief explanation of Flaxseed (linseed, linum usitatissimim) with information as to the health benefits listed for the food. I will investigate the possible connection between dietary intake of flaxseed and the benefit for cardiovascular health.
Section 2 of this paper will delve into current studies on whether flaxseed will diminish atherosclerosis thereby reducing the number of deaths by heart disease. The third section discusses the importance of dietary flaxseed supplementation (ALA) for helping reduce cholesterol levels promoting a healthier heart. A summary of all key points will follow, providing a brief but thorough recap of the entire document.
Many people worldwide are plagued with having to make decisions to eat processed, packaged and fast foods resulting in a high risk of cardiovascular disease. More women die from cardiovascular disease than from all forms of cancer combined(Balch, 2010). Despite the remarkable technology that exists today, the first sign of cardiovascular disease may be life-threatening. Cardiovascular disease is responsible for at least forty-three percent of all deaths in the United States(Murray, 1998). Imagine if just adding this small little seed, ground up to your salads, potatoes, smoothies could improve the lives of so many and prevent many others from living a life of increased risk of heart disease, wouldn’t it be worth it.
Heart Disease is a term often used to describe atherosclerosis. Atherosclerosis is the hardening of the artery walls due to a build-up of plaque, which contains cholesterol, fatty material and debris. Other concerns with Cardiovascular disease are congestive heart failure, arrhythmias, mitral valve prolapsed, and cardiomyopathy. This disease is the leading cause of mortality worldwide, and is responsible for as many as 500 000 deaths of women in the US yearly(Balch, 2010).
Elevated blood cholesterol levels greatly increase the risk of death due to heart disease. For every one percent drop in LDL cholesterol, the risk for a heart attack drops by 2 percent. For every 1 percent increase in HDL the risk for a heart attack drops three to 4 percent (Murray, 1998). Diets high in omega-3 oils from fish or veggies have reduced risk of developing heart disease. Omega 3 fatty acids lower levels of LDL cholesterol and triglycerides,(Murray, 1998) and so it has been stated that patients with heart disease who took 1 gram of omega-3s had fewer deaths and admissions to the hospital for treatment of their heart disease (Balch, 2010).
Flaxseed (linseed, linum usitatissimim) is an edible oil seed/grain that has been recently acknowledged as a beneficial food. It has gained much attention because of its unique nutrient components. Flaxseeds are the most concentrated plant source of the omega-3 fatty acid, alpha-linolenic acid (ALA) and are an essential source of dietary fibre. ALA comprises approximately 55% of the total fatty acid content of flaxseed fatty acids. ALA is a precursor to the omega-3’s that are found in cold water fish, which is known for their anti-inflammatory properties (Mateljan, 2007). According to the World Health Organization, Flaxseeds contain lignans which provide many health benefits. They are said to promote Heart Health as the ALA is associated with a lower risk of developing plaque and dying for heart disease. ALA helps to lower cholesterol and provide protection against heart disease. They are also full of folate, magnesium and vitamin B6 which are all necessary to have a healthy heart.
Therefore, an investigation is necessary to see if consuming quantities of flaxseed will help to reduce plaque, lower cholesterol, improve your overall heart health and diminish signs of atherosclerosis.
Consuming omega-3 is promoted as providing cardioprotection against heart disease. Recently, flaxseed has been promoted as a beneficial alternative source as it is one of the richest sources of ALA which has been identified in several epidemiological trials as having beneficial effects against heart disease and in decreasing signs of atherosclerosis.
In 2011, an investigation was completed on the effects of dietary flaxseed with and without a diet enriched with cholesterol. In this test, 8 rabbits were given one of four randomly assigned diets, either a control, a diet with cholesterol added, a diet with flaxseed added or a diet with both cholesterol and flaxseed added. Following the 8 weeks, testing revealed that consumption of flaxseed significantly increased plasma and adipose levels of ALA therefore decreasing the percentage of atherosclerotic plaque in the rabbit. The results of this study, give a p value of less than 0.05 indicating that there is only a 5% probability that the differences they received is due to chance. This is a very good indication of strong results; however, with a testing on just 8 mice, more study should be completed (McCullough, Edel, Bassett, Lavallée, Dibrov, Blackwood, Ander, Pierce, 2011).
Despite studies showing that there would be a reduction of plaque formation with the consumption of flaxseed, there was still much debate as to the true benefits and whether Flax could inhibit atherosclerosis. According to study posted in the American Journal of Physiology in 2007, using cholesterol fed rabbits to model human atherosclerosis is not an ideal representation. Genetically manipulated mouse models such as the LDL receptor-deficient (LDLrKO) would be a closer representation to the human condition. As such, they completed a similar study but using LDLrKO mice as it only develops diet-induced atherosclerotic lesions. These mice were also administered various diets either consuming of flaxseed, cholesterol, a combination of both, or a regular diet. Coconut oil was also used for one group as a means of a control. The purpose was to assess the antiatherogenic effects of dietary flaxseed on the mice in order to determine the mechanism of action of flaxseed at a cellular level. This well-designed study used 100 female mice, randomly assigned 1 of 7 dietary treatment groups following a 1 week acclimatization period. Mice consumed 4g of diet daily. Temperature was controlled and ethical standards followed. Following 24 weeks, tissue, plasma and lesions size was measure.
The results of this study indicated that flaxseed decreased the omega 6/omega 3 ratio in plasma, and it increased plasma ALA and EPA. The cholesterol group did not increase ALA. Flaxseed did not alter plasma cholesterol when taken by itself, but when taken with cholesterol the flaxseed mitigated the hypercholesterolemic effect. Additionally, flaxseed showed a protective effect against atherosclerosis as well as showed an anti-proliferation and anti-inflammatory action. The researches of this study provided p values of less than 0.05 giving the study even more certainty indicating that there is 95% likelihood that the results are real. As such, this study demonstrated that dietary flaxseed can inhibit atherosclerosis in the LDLrKO mouse through a reduction of circulating cholesterol levels and, at a cellular level, through anti-proliferative and anti-inflammatory actions (Duspasquier, Dibrov, Kneesh, Cheung, lee, Alexander, Yeganeh, Mohgadasian, 2007). However, further studies should be completed using male mice to conclude the effectiveness on either gender.
In response to the previous research, LT Bloedon et Al set out to complete the first clinical trial on the benefits of flaxseed against cardiovascular risk factors. These researches agreed that the alpha linolenic acid (ALA) content of flaxseed in combination with the fiber and lignans make it a very desirable food that could potentially reduce cardiovascular risk. Conducted at the University of Pennsylvania, this double blind, randomized controlled clinical trial brought more confirmation to the already existing research completed on rabbits and mice. This study was completed on 62 men and women who had all been diagnosed with hypercholesterolemia, or high levels of LDL cholesterol, and were at risk of cardiovascular disease. For 10 weeks participant’s diets were low fat and low cholesterol and they were given either given 40g of ground flaxseed daily or wheat bran daily for 10 weeks. As with the previous studies testing was completed to measure inflammation and lipoprotein levels. Results concluded that ground flaxseed could lower LDL cholesterol levels substantially in the short term; however its effect seems to dissipate in the long term. Flaxseed increased ALA levels in the blood, reduced lipoprotein by 14% and improved insulin resistance by 24%; however this test did not show any affect on inflammation. The researches give promising results especially with p values of 0.01, 0.05, 0.02 and 0.03 indicating that they are confident that the results are real and not due to chance (Bloedon, Balikai, Chittams, Cunnane, Berlin, Rader, Szapara, 2008). From this we can see that there is reason to consume ground flaxseed in order to get a reduction in cardiovascular disease, however, more studies can be completed to see if consuming ground flaxseed can ward of the development of cardiovascular disease in today’s society.
The data provided from the various studies supports even more direct evaluation of the anti-atherogenic potential of dietary flaxseed for humans. It has been demonstrated through testing that supplementing with 20-50grams of ground flaxseed daily can reduce LDL cholesterol and reduce atherosclerotic plaques in mice, rabbits and people.
From these studies, we can determine that the cholesterol-lowering effect of flaxseed is one of the main contributing factors however additional mechanisms at the cellular level, such as its anti-proliferative and anti-inflammatory effects are likely all responsible flaxseeds atherosclerotic effect. Despite the testing, more studies are required using human trials to determine the true ability of ground flaxseed to inhibit atherosclerosis altogether, however, there is definitely a positive effect and so consuming ground flaxseed daily can be recommended.
Conclusion / Bringing it All Together
This paper reviewed three cases in which dietary flaxseed were shown to reduce or inhibit the atherogenic effects of high cholesterol. Studies were completed on LDLrKO mouse, on white rabbits and on people with atherosclerosis. The results of these studies showed an improvement in cholesterol levels and indicated that consumption of this seed can inhibit cell proliferation and inflammation. Since these studies have been completed to evaluate the effects of flaxseed in more than 1 animal, and now with humans, further trials should be completed using double blind, controlled studies on human populations both with and without signs of cardiovascular disease to see if consuming ground flaxseed can ward of the development of cardiovascular disease in today’s society.
Regardless of still existing uncertainties we can be assured that consuming ground flaxseed will not be deemed harmful to the body in any way. It is important to remember that the ALA found in flaxseed is the agent which converts to the omega 3 fatty acids EPA & DHA, and therefore if a person has a problem with the mechanism to convert, Flaxseed supplementation would not be as beneficial. With that being said, this food is filled with nutrients and dietary fibre in addition to the possible beneficial effects for cardiovascular health.
Full Reference List
Balch, P.A. (2010). Prescription for nutritional healing. Cardiovascular Disease (pp.306-318) New York, NY: Penguin Group
Bloedon, LT., Balikai, S., Chittams, J., Cunnane, SC., Berlin, JA., Rader, DJ., & Szapara, PO. (2008). Flaxseed and cardiovascular risk factors: results from a double blind, randomized, controlled clinical trial. Journal of the American College of Nutrition, 27(1), 65-74
Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/18460483
Dupasquier, CM., Dibrov, E., Kneesh AL., Cheung, PK., Lee, KG., Alexander, HK., Yeganeh, BK., Moghadasian, MH., Pierce, GN. (2007). Dietary flaxseed inhibits atherosclerosis in the LDL receptor-deficient mouse in part through antiproliferative and anti-inflammatory actions. Amercican Journal of Physiology: Heart and circulatory Physiology, 293(4): H2394-402
Retrieved from: http://www.ncbi.nlm.nih.gov/pubmed/17616740
Mateljan, G. (2007). Worlds healthiest foods. Seattle, Washington: George Mateljan Foundation
McCullough, RS., Edel, AL., Bassett, CM., Lavallée, RK., Dibrov, E., Blackwood, DP., Ander, BP., Pierce, GN. (2011) The alpha linolenic acid content of flaxseed is associated with an induction of adipose leptin expression. American Journal Of Physiology. 46(11): 1043-52.
Retrieved from: http://www.ncbi.nlm.nih.gov/pubmed/22031167