Science Meets Fitness & Exercise
Superfoods:Benefits of Garlic
Made famous by vampire movies, Garlic is much like Marmite; you either love it or you hate it. Allium sativum or Garlic is a food type from the ‘Allium’ onion range, along with foodstuffs such as scallion, shallot, leek, and chives. Garlic is a highly potent foodstuff with a distinctive taste and pungent smell. Garlic is used extensively in Korean, Chinese and Italian recipes and is one of the most popular food additions for adding a specific taste to recipes. However, Garlic is far more than simply a food ‘additive’ and has many proven health qualities that bring it into the scope of being a ‘superfood’. Let’s look at some of the claims for this onion derivative and analyse the accuracy behind such claims.
A Compound Called Allicin
When Garlic is crushed, or chopped Alliin (sulfoxide that is a natural constituent of fresh garlic) comes into contact with the enzyme Allinase, which converts Alliin to Allicin. The compound Allicin has been widely linked to many health-based benefits including Antibacterial, Antifungal and Antiviral properties.
Many studies have linked Allicin as having anti-bacterial properties. Ankri et al (1999) determined that Allicin,
‘Exhibited antibacterial activity against a wide range of Gram-negative and Gram-positive bacteria, including multidrug-resistant enterotoxicogenic strains of Escherichia coli’
The same study also identified anti-fungal properties ‘particularly against Candida albicans’. This study determined that Allicins main effect was due to its ‘chemical reaction with groups of various enzymes’, for example, ‘alcohol dehydrogenase, thioredoxin reductase, and RNA polymerase’.
Other studies have found similar findings including, Ankri S. et al (1997), Mirelman D. et al (1987) and Fujisawa H. (2009)
Garlic indeed seems to be a highly potent foodstuff in respect of reducing the potential of fungal, bacterial and viral infections and so is highly important in terms of immunity and reducing the possibility of becoming ‘ill’.
Reduction of Bad Cholesterol (LDL)
Cholesterol is a wax-like fatty substance produced naturally in the body by the liver and small intestine, and is also introduced to the body through nutritional intake. It comes in two distinct formats which are known as ‘bad cholesterol’ and ‘good cholesterol’. Bad cholesterol or Low-Density Lipoproteins (LDL) makes up the majority of the bodies cholesterol. Although LDL cholesterol is an important essential fat that is vital to body cells, it is also the cholesterol that builds up as plaque on blood vessel walls causing conditions such as atherosclerosis. Good cholesterol or High-Density Lipoproteins (HDL) are considered to mediate some positive health benefits to the cardiovascular system. It is believed HDL cholesterol removes LDL cholesterol from the blood by transporting it to the liver and ‘recycling’ it. HDL cholesterol also repairs damage to blood vessel walls within the endothelium; thus diminishing the incidence of atherosclerosis. In modern western societies, cholesterol has become a curse in the day to day diets of individuals. Butter, cheese, fatty milk and many red types of meat are indicative of high cholesterol sources.
Garlic has been identified in some studies, with potential reductions in bad cholesterol. Yeh Y.Y (1994) determined that garlic can lower cholesterol levels,
‘Results suggest that the hypocholesterolemic effect of garlic stems, in part, from decreased hepatic cholesterogenesis, whereas the triacylglycerol-lowering effect appears to be due to inhibition of fatty acid synthesis’.
However, the predominance of research, Van Doorn M, (2006), Christopher D. Gardner et al (2007) has determined that Garlic does not have the potential to lower cholesterol and so in this instance Garlic cannot be recommended as a health benefit in relation to cholesterol.
MMA
Reduction of Blood Pressure
High blood pressure is one of the blights of modern day ‘man’. Poor diet, smoking, excess alcohol and sedentary lifestyles can all lead to high blood pressure and increased medical implications such as, weakening of the brains blood vessels which can lead to potential stroke. Constricted blood vessels through atherosclerosis in combination with high blood pressure can also have numerous cardiovascular risk factors. Drugs such as beta blockers can be used to reduce blood pressure but why not try and utilise a natural; blood pressure ‘reducer’ and avoid the side effects of medicinal drugs. This is where Garlic might be a natural health benefit. Studies have illustrated that Garlic has numerous cardiovascular benefits.
Ried, K. (2010) carried out a study in order to,
‘Assess the effect, tolerability and acceptability of aged garlic extract as an adjunct treatment to existing antihypertensive medication in patients with treated, but uncontrolled, hypertension’.
They determined that,
‘Aged garlic extract is superior to placebo in lowering systolic blood pressure similarly to current first line medications in patients with treated but uncontrolled hypertension.’
Reid, K. (2016) also carried out a meta-analysis on studies ranging from 1955 to 2013. Their analysis of over 20 individual trials determined that,
‘Garlic supplements have the potential to lower blood pressure in hypertensive individuals, to regulate slightly elevated cholesterol concentrations, and to stimulate the immune system. Garlic supplements are highly tolerated and may be considered as a complementary treatment option for hypertension’.
Some studies have provided opposite conclusions Turner B. et al (2004) to these studies but the predominance of the evidence is ‘pro’ garlic and cardiovascular benefits.
Sports Performance Enhancement
A few studies have determined that Garlic does have the potential to improve physical performance. Naoaki Morihara (2006) determined that,
‘Aged garlic extract may facilitate the turnover of aerobic glucose metabolism, attenuate oxidative stress, and promote oxygen supply based on vasodilation, suggesting that AGE ameliorates the various impairments associated with physical fatigue.’
Deniz, I. et al (1999) carried out a study regarding the effects of a single dose (900-mg) of Garlic powder on performance within an incremental treadmill exercise test. The researchers concluded that,
‘The administration of single dose of garlic was shown to increase VO2max and endurance performance time of college endurance athletes during a treadmill running test according to the Bruce protocol.’
Other studies have concurred with this research, Sookvanichsilp N. (2002), Verma S.K. (2005), Punduk, Z. (2016) among many others. The consensus is that garlic does indeed enhance many parameters of physical performance.
Garlic Can Enhance Physical Performance
Summary
Garlic has many food enhancing properties from the taste to the aroma. But it also has many proven health benefits including the ability to reduce chance of illness, reduce the symptoms of illness and indeed enhance physical performance. It has earned respect and its place in the esteemed ‘hall’ of ‘superfoods’.
Garlic is Indeed One of the 'Superfoods'
References
Ankri S., Miron T, Rabinkov A, Wilchek M, Mirelman D. (1997) Allicin From Garlic Strongly Inhibits Cysteine Proteinases And Cytopathic Effects Of Entamoeba Histolytica. Antimicrob Agents Chemother. Oct;41(10):2286-8.
Christopher D. Gardner, PhD; Larry D. Lawson, PhD; Eric Block, PhD; et al (2007) Effect Of Raw Garlic Vs Commercial Garlic Supplements On Plasma Lipid Concentrations In Adults With Moderate Hypercholesterolemia, Arch Intern Med;167(4):346-353
Deniz, N. Tiryaki, G. Levent, M. (1999) Effects of Garlic on Aerobic Performance. Turk J Med Sci. 30 (2000) 557-561
Mirelman D, Monheit D, Varon S. (1987) Inhibition Of Growth Of Entamoeba Histolytica By Allicin, The Active Principle Of Garlic Extract (Allium Sativum). Journal of Infectious Diseases. Jul;156(1):243-4.
Naoaki Morihara, Mitsuyasu Ushijima, Naoki Kashimoto, Isao Sumioka, Takeshi Nishihama, Minoru Hayama, Hidekatsu Takeda (2006) Aged Garlic Extract Ameliorates Physical Fatigue. Biological and Pharmaceutical Bulletin. Volume 29 (2006) Issue 5 Pages 962-966
Reid, K. (2016) Garlic Lowers Blood Pressure in Hypertensive Individuals, Regulates Serum Cholesterol, and Stimulates Immunity: An Updated Meta-analysis and Review. J Nutr. Feb;146(2):389S-396S
Sookvanichsilp N., Tiangda C, Yuennan P. (2002) Effects of Raw Garlic On Physical Performance And Learning Behaviour In Rats. Phytother Res. Dec;16(8):732-6.
Turner B., Mølgaard C, Marckmann P. (2004) Effect Of Garlic (Allium Sativum) Powder Tablets On Serum Lipids, Blood Pressure And Arterial Stiffness In Normo-Lipidaemic Volunteers: A Randomised, Double-Blind, Placebo-Controlled Trial. Br J Nutr. Oct;92(4):701-6.
Van Doorn M, Santo SM, Meijer P. (2006) Effect Of Garlic Powder On C-Reactive Protein And Plasma Lipids In Overweight And Smoking Subjects American Journal Of Clinical Nutrition, December 84:1324-1329.
Verma S.K., Rajeevan V, Jain P, Bordia A. (2005) Effect Of Garlic (Allium Sativum) Oil On Exercise Tolerance In Patients With Coronary Artery Disease. Indian J Physiol Pharmacol. Jan;49(1):115-8.
Yeh Y.Y., Yeh S.M. (1994) Garlic Reduces Plasma Lipids By Inhibiting Hepatic Cholesterol And Triacylglycerol Synthesis. Lipids. Mar;29(3):189-93.
Punduk, Z. (2016) Aged Garlic Supplementation Improves Muscle Performance Properties in Untrained Male. Electronic J Biol, 12:3