Flavour of the Week

Who’s Up For Coconut Oil?


Formerly associated with greased up bodybuilders and sunbathing beauties, coconut oil and its related products like coconut water are now making a splash in the nutrition world. Aside from skin and hair care, the internet abounds with the so-called benefits of nutritional coconut products – from weight loss and heart health to immunity and digestion.

So, how exactly did a once-questionable saturated fat become the in vogue go-to for health? How much is hype vs. scientifically established evidence?

Coconut products, like coconut oil, milk and water are commonly consumed in Asia, particularly Southeast Asia and India, as well as the Caribbean. They have long been touted as “antibacterial, antifungal, antiviral, antiparasitic, antidermatophytic, antioxidant, hypoglycemic, hepatoprotective and immunostimulant” (1) but there is surprisingly little research evidence to back up most of these claims.

Nutrient Composition

Coconut oil
An edible oil extracted for the meat of mature coconuts, coconut oil is solid at room temperature owing to its nearly 87% saturated fat content; though most is in the form of lauric acid, a medium-chain triglyceride (12 carbon chain). It is the presence of these medium chain triglycerides (MCTs) that are proposed to account for coconut oil’s “health benefits” compared with other solid fats like butter.

………………
1 tbsp*
Calories Fat.. Saturated MCTs
Coconut oil 119 kcal 14 g 12 g 8.1 g
Butter 102 kcal 12 g 7.4 g 1.7 g

*nutritional information from Canadian Nutrient File (2010)

MCTs are six to 12 carbons long, which is shorter than most triglycerides found in food (for example, the omega-3 fatty acid DHA is 22-carbons long). As a result these shorter chains allow for passive absorption in the gut and do not need bile salt emulsifying – MCTs are known to be extremely beneficial in fat malabsorption syndromes and malnutrition owing to this easy absorption.

If you want to give coconut oil a try, make sure you buy the virgin coconut oil, not partially hydrogenated varieties, which contain trans fat.

Coconut water
Coconut water is the clear liquid inside young coconuts. It is a great source of fluids and potassium, relatively low calorie with decent mineral content (like magnesium and phosphorus) but a low level of vitamins. Commercial varieties include those with and without “pulp” or puree added; the chief difference being additional calories and fibre.

……………………
250 ml*
Calories Carbs Potassium Sodium
Coconut water 45 kcal 11 g 470 mg 30 mg
Orange juice 118 kcal 27.3 g 524 mg 3 mg
Sport drink 67 kcal 17 g 39 mg 101 mg

*nutritional information from Canadian Nutrient File (2010) and the Vita Coco website

Many internet sites also claim that coconut water is rich in antioxidants though we could not find any documentation to support this. Make sure to compare labels and ingredients as some coconut water brands have added sugar and preservatives, particularly in fruit-flavoured options. Likewise, calorie and electrolyte content can vary widely – 100% coconut water may be higher in calories than those made from concentrate and diluted with water.

Coconut oil and cholesterol
Despite being predominantly saturated fat, it seems there just might be something to the claim that coconut oil doesn’t behave like typical saturated fats with respect to cholesterol levels.

Several studies have linked a rise in total cholesterol level with coconut oil consumption BUT this rise in total cholesterol is largely due to an increase in “good” HDL cholesterol (2,3,4). Similarly, Voon et al. (5) demonstrated that lauric acid consumption, the predominant saturated fat in coconut oil, may not increase inflammatory markers like other saturated fats do.

Caution must be used when interpreting this data, however, as no long term studies have  looked at coconut oil and actual health outcomes, such as incidence of heart disease or stroke. Palm oil is another saturated fat-rich tropical oil (primarily 16-carbon palmitic acid) that some preliminary, short-terms studies suggested did not increase “bad” LDL levels (6), yet a recent population-based study has linked consumption of palm oil to an increased risk of cardiovascular disease (7).

Coconut products and weight loss
The power of testimonials! While Madonna and other celebrities may promote coconut water as the end-all-be-all of weight loss, to date no studies have actually assessed coconut water consumption and weight loss. (Side note: Madonna also owns Vita Coco, so that might be part of the promo splash!). Coconut water can be a potent laxative when consumed in large quantities and has historically been used as a treatment for constipation, so perhaps that has something to do with the anecdotal weight loss!

Coconut oil, owing to its MCT content, has also been touted as a weight loss agent. In a classic don’t-just-read-the-abstract study, a double-blind RCT of 30 ml coconut oil vs. soybean oil (in combination with calorie restriction and exercise) found that the coconut oil group showed a reduction in waist circumference. When you read the actual article, however, this was after only one week of supplementation (!) and the difference in waist circumference, though “statistically significant” was relatively minor (especially given that standard deviation was five-fold higher!) (2). Think about how different your pants can fit from day-to-day…

While some groups suggest that MCTs have a beneficial impact on satiety, fat oxidation and energy expenditure, a recent systematic review indicates that while use of MCTs in obesity treatment is promising, results remain inconclusive and more research is needed (8). Sound familiar?

Coconut water as a sports drink
Given its high levels of the electrolyte potassium, some groups suggest that coconut water offers optimal hydration for athletes and is a suitable and “natural” alternative to commercial sports drinks. Of course, the relative lack of sodium in coconut water is an obvious, and often ignored, concern given the importance of sodium replacement with strenuous activity!

A recent study found no difference in hydration status or performance when coconut water was compared with a standard sport drink or bottled water for rehydration after a dehydrating-exercise challenge, though more bloating and stomach upset were reported in the coconut water group (9). When compared to plain old water or sports drinks, Saat et al. (10) also found that coconut water was no different in terms of rehydration after exercise.

So, shouldn’t there be a difference? One would think that a sports drink would come out tops for rehydrating because of the sodium content, so these results are intriguing. Keep in mind that these two studies were rehydration interventions and participants lost > 2% body weight during short-bout exercise (60 minutes), which is considered excessive (12). Current guidelines suggest that you replace fluids throughout activity, especially if greater than one hour, to prevent such huge fluid losses. In other words – don’t try this at home! For optimal performance, guidelines recommend sodium replacement for activity over one hour or if you are a heavy sweater (11,12).

Some argue that the potassium in coconut water can be helpful for those prone to muscle cramping, but studies have recently shown that exercise-associated muscle cramping, contrary to popular belief, may have relatively little to do with electrolyte balance (13). As for now, we will have to wait for additional studies to look at hydration during activity with coconut water and any impact on performance.

No Baloney’s advice. Like any fat, coconut oil should be used in moderation. Given the lack of long-term studies, we don’t suggest scrapping the olive oil just yet! Use sparingly because it still packs a lot of calories, but can be a tasty substitute for butter in some baked goods (like our Pina Colada Spelt Loaf).

Although coconut water is an option to boost your fluid intake, it is not calorie-free! While lower in calories than fruit juice, we still suggest mixing with water; keep an eye on the quantity you drink to avoid any stomach upset too. Coconut water is not a sports drink replacement, unless you are working out for less than one hour and don’t need the sodium… in which case, water is still your best (and cheapest!) option.

References:

  1. DebMandal M, Mandal S. Coconut (Cocos nucifera L.: Arecaceae): in health promotion and disease prevention. Asian Pac J Trop Med 2011; 4:241-7.
  2. Assunção ML, et al. Effects of dietary coconut oil on the biochemical and anthropometric profiles of women presenting abdominal obesity. Lipids 2009; 44:593-601.
  3. Feranil AB, et al. Coconut oil is associated with a beneficial lipid profile in pre-menopausal women in the Philippines. Asia Pac J Clin Nutr 2011; 20:190-5.
  4. Mensink RP, et al. Effects of dietary fatty acids and carbohydrates on the ratio of serum total to HDL cholesterol and on serum lipids and apolipoproteins: a meta-analysis of 60 controlled trials. Am J Clin Nutr 2003; 77:1146-55.
  5. Voon PT, et al. Diets high in palmitic acid (16:0), lauric and myristic acids (12:0+14:0), or oleic acid (18:1) do not alter postprandial or fasting plasma homocysteine and inflammatory markers in healthy Malaysian adults. Am J Clin Nutr 2011; 94:1451-7.
  6. Clandinin MT, et al. The effect of palmitic acid on lipoprotein cholesterol levels. Int J Food Sci Nutr 2000; 51:S61-71.
  7. Chen BK, et al. Multi-Country analysis of palm oil consumption and cardiovascular disease mortality for countries at different stages of economic development: 1980-1997. Global Health 2011; 7:45.
  8. Rego Costa AC, et al. Influence of the dietary intake of medium chain triglycerides on body composition, energy expenditure and satiety: a systematic review. Nutr Hosp 2012; 27:103-8.
  9. Kalman DS, et al. Comparison of coconut water and a carbohydrate-electrolyte sport drink on measures of hydration and physical performance in exercise-trained men. J Int Soc Sports Nutr 2012; 9:1.
  10. Saat M, et al. Rehydration after exercise with fresh young coconut water, carbohydrate-electrolyte beverage and plain water. J Physiol Anthropol Appl Human Sci 2002; 21:93-104.
  11. American Dietetic Association, Dietitians of Canada and American College of Sports Medicine. Nutrition and athletic performance joint position statement. Medicine & Science in Sports & Exercise 2009; 41:709-31.
  12. American College of Sports Medicine. American College of Sports Medicine position stand: exercise and fluid replacement. Med Sci Sports Exerc 2007; 39:377-90.
  13. Schwellnus MP, et al. Increased running speed and previous cramps rather than dehydration or serum sodium changes predict exercise-associated muscle cramping: a prospective cohort study in 210 Ironman triathletes. Br J Sports Med 2011; 45:650-6.
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