This delicious low carb high fat Matcha Smoothie can help you lose weight & abdominal fat. The science behind it, the recipe & the nutritional info in this article.
Green tea is the unfermented leaves of the Camellia sinensis plant and contains a number of biologically active compounds called catechins of which epigallocatechin gallate (EGCG) makes up ~ 30% of the solids in green tea [Kim et al]. Studies have found that green tea catechins, especially EGCG play a significant role in both weight loss and lower body fat composition.
Population studies and several randomized controlled studies (where one group is “treated” and the other group is not) have shown that waist circumference is smaller and levels of body fat is less the more green tea consumed [Phung et al]. The anti-obesity effects of green tea are usually attributed to the presence of catechins [Naigle].
Several large-scale population studies have linked increased green tea consumption with significant reductions in metabolic syndrome – a cluster of clinical symptoms which include insulin resistance or hyperinsulinemia (high levels of circulating insulin), Type 2 Diabetes, hypertension or high blood pressure, cardiovascular disease including coronary heart disease and atherosclerosis.
It is thought that epigallocatechin gallate (EGCG), the most abundant catechin in green tea, mimics the actions of insulin. This has positive health implications for people with insulin resistance or Type 2 Diabetes [Kao et al].
EGCG also lowers blood pressure almost as effectively as the ACE-inhibitor drug, Enalapril, having significant implications for people with hypertension (high blood pressure) and cardiovascular disease [Kim et al].
Research indicates that drinking 8-10 cups of green tea per day is enough to increase blood levels of EGCG into a measurably significant range [Kim et al].
The most effective way to reduce the symptoms associated with metabolic syndrome is through a low carb high healthy fat diet, however the addition of green tea as a beverage – especially as matcha green tea powder, may provide a means to preferentially target abdominal weight loss.
GREEN TEA CATECHINS
Catechins make up ~ 30% of green tea’s dry weight (of which 60–80% are catechins) and oolong and black tea (which are produced from partially fermented or completely fermented tea leaves) contains approximately half the catechin content of green tea.
Matcha, a powdered green tea used in the Japanese tea ceremony and popular in cold green tea beverages contains 137 times greater concentration of EGCG than China Green Tip tea (Mao Jian) [Weiss et al].
GREEN TEA CATECHIN CONTENT OF BREWED GREEN TEA VS MATCHA POWDER
A typical cup (250 ml) of brewed green tea contains 50–100 mg catechins and 30–40 mg caffeine, with the amount of tea leaves, water temperature and brewing time all affecting the green tea catechin content in each cup.
A gram (~1/3 tsp) of matcha powder contains 105 mg of catechins – of which 61 mg are EGCGs and contains 35 mg of caffeine. Most matcha drinks made at local tea and coffee houses are made and served cold and contain ~1 tsp of matcha powder which contains ~315 mg of catechins – of which ~183 mg are EGCs.
WEIGHT LOSS EFFECT OF GREEN TEA CATECHINS
A 2009 meta-analysis (combining the data from all studies) of 11 green tea catechin studies found that subjects consuming between 270 to 1200 mg green tea catechins / day (1 – 4 tsp of matcha powder per day) lost an average of 1.31 kg (~ 3 lbs) over 12 weeks with no other dietary or activity changes [Hursel].
Body composition EFFECT OF GREEN TEA CATECHINS
The effect of green tea catechins on body composition is significant – even when the weight loss between “treated” and “untreated” groups is small (~5 lbs in 12 weeks).
Even with such small amounts of weight loss;
– the total amount of abdominal fat decreased 25 times more with green tea catechin consumption than without it (−7.7 vs. −0.3%)
– total amount of subcutaneous abdominal fat (the fat just below the skin of the abdomen) decreases almost 8 times more with green tea catechin consumption than without it (−6.2 vs. 0.8%).
HOW DO GREEN TEA CATECHINS WORK?
The mechanisms by which green tea catechins reduce body weight and reduce the amount of total body fat and in particular reduce the amount of abdominal fat are still being investigated. It is currently thought that green tea catechins;
– increased thermogenesis; i.e. increased heat production which would result in increased energy expenditure (or calorie burning)
– increase fat oxidation i.e. using body fat as energy. For those on a low fat high fat diet, this is good!
– decrease appetite
– down-regulation of enzymes involved in liver fat metabolism (fat storage)
WARNING TO PREGNANT WOMEN
While EGCG has also been found to be similar in its effect to etoposide anddoxorubicin, a potent anti-cancer drug used in chemotherapy [Bandele et al], high intake of polyphenolic compounds during pregnancy is suspected to increase risk of neonatal leukemia. Bioflavonoid supplements (including green tea catechins) should not be used by pregnant women [Paolini et al].
Low Carb Green Tea Matcha Smoothie Recipe
Total carbs: 2.5 gm per serving – contains ~315 mg catechins
1 tsp matcha (green tea) powder * (1 tsp = 2 gm)
12 cubes ice, crushed
1/2 cup (125 ml) coconut milk
optional: 1/2 tsp Silan (Middle Eastern date syrup) – will add an additional 3.5 g carbs to the recipe
- Place 1 tsp matcha powder in a small stainless steel sieve and gently press through the sieve into a small bowl with the back of a small spoon
- Put the sieved matcha powder into a ceramic or glass bowl (not metal, as the tannins in the tea will react and give the beverage and “off” metalic taste)
- With a bamboo whisk (available at Japanese and Korean grocery stores) or a plain spoon, whisk 3 Tbsp boiled and cooled water into the matcha powder, until all the lumps are gone and the mixture is smooth
- Place a whole tray of ice cubes (12) into a blender
- Pour matcha and water mixture over ice in the glass
- Pour coconut milk on top of ice and matcha
- Pulse until desired texture is achieved*
*I blend mine just fine enough to be able to drink it through a straw.
Saturated Fat 7.7 gm
Cholesterol 0 mg
Sodium 7.5 mg
Carbohydrates 1 gm
Dietary Fiber 770 mg
Protein 1.1 gm
Calcium 8.8 mg
Vitamin A (Retinol Equivalents) 198.4 mg
B-Carotene 1.2 gm
Magnesium 4.6 mg
Vitamin B1 .12 mg
Potassium 54 mg
Vitamin B2 .027 mg
Phosphorus 7.0 mg
Vitamin B6 .018 mg
Iron .34 mg
Vitamin C .12 mg
Sodium .12 mg
Vitamin E .562 mg
Zinc .126 mg
Vitamin K 58 mcg
Copper .012 mg
Polyphenols 200 mg
Caffeine 50 mg
Theophylline 0.84 mg
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