Once again, green smoothies have come under fire, and their health benefits are being questioned by various bloggers and health experts on the internet. Victoria Boutenko addresses the four main claims, and provides some food for thought in her green smoothie blog.
From Victoria’s blog here: http://greensmoothiesblog.com/victorias-response-to-criticism-of-green-smoothies/
“Hundreds of thousands of people around the globe are happily consuming green smoothies. My inbox is overflowing with testimonials of amazing recoveries that I receive daily from green smoothie drinkers. We have videotaped testimonials from people who started drinking green smoothies and were able to reverse heart disease, stroke, hypertension, diabetes type II, and many other conditions.
However, as Franklin D. Roosevelt said, “There are as many opinions as there are experts.” For this reason, once in a while I run into counter claims. Below are my answers to some of them.
1. Claim: Blending destroys fiber.
My answer: I verified what science has to say about blending fiber. I was able to find several studies that conclude that “particle size of the fiber source did not affect performance.” (1) The most interesting research article I found was from, “Gut,” an international peer-reviewed journal for health professionals and researchers in gastroenterology & hepatology. Volume 37, Issue 2: “Effect of bran particle size on gastric emptying and small bowel transit in humans.” Authors R Vincent, A Roberts, et al, compared bran particles of 2 mm to less than .7 mm.
This study found that both fine and coarse fiber have only 2% difference in performance, favoring the smaller fiber. Moreover, the researchers stated “Fine bran causes less disturbance of gastric physiology than coarse bran” (2) and discussed how finely ground fiber increases nutrient absorption, and reduces bloating, heartburn, and constipation.
2. Claim: Blending destroys 90% of nutrients.
In an interview, two respectable doctors bring a wealth of information on a natural healing. Towards the end of the interview, Dr. Clement states that “blending your veggies using a blender can kill up to 90 percent of the nutrients in 90 seconds.” Next, in contradiction to his own statement he explains, that “vitamins A, E, C; the basic five nutrients are killed in 90 seconds of blending with a high-speed blender.”
There is a big difference between these two statements:
• blending can kill up to 90 percent of [all] the nutrients;
• 90 percent of the basic five nutrients are killed by blending
There are many studies done in the US, in Netherlands, and in other countries. For example, here is one scientific study, which compares blending and juicing. In the following statement (I have highlighted the most important content.)
“Due to the consumer’s interest in obtaining high levels of phytochemicals, it is important to understand the changes in their levels by common household processing techniques. Therefore, mature Texas “Rio Red” grapefruits were processed by some of the common household processing practices such as blending, juicing, and hand squeezing techniques and analyzed for their phytochemical content by high performance liquid chromatography (HPLC). Results suggest that grapefruit juice processed by blending had significantly (P < 0.05) higher levels of flavonoids (narirutin, naringin, hesperidin, neohesperidin, didymin, and poncirin) and limonin compared to juicing and hand squeezing. No significant variation in their content was noticed in the juice processed by juicing and hand squeezing. Ascorbic acid and citric acid were significantly (P < 0.05) higher in juice processed by juicing and blending, respectively. Furthermore, hand squeezed fruit juice had significantly higher contents of dihydroxybergamottin (DHB) than juice processed by juicing and blending. Bergamottin and 5-methoxy-7 gernoxycoumarin (5-M-7-GC) were significantly higher in blended juice compared to juicing and hand squeezing. Therefore, consuming grapefruit juice processed by blending may provide higher levels of health beneficial phytochemicals.” (3)
From my personal observation, I seriously doubt that blending destroys vitamin C because I witnessed countless times how people who consume green smoothies on a regular basis, tested outstandingly high both in vitamin C and in antioxidants tests.
3. Claim: Oxalic acid in spinach and other greens cause kidney stones
To answer this claim, I have written an article where I present lots of citations from original research documents.
About 85% of all kidney stones contain calcium salts, calcium oxalate and/or calcium phosphate. It seems logical to connect calcium oxalate with oxalic acid in some foods, such as spinach, soy, tea, coffee, wheat, and some others. However, you will not find any scientifically documented evidence that oxalic acid in food causes the formation of kidney stones. On the contrary, substantial scientific research in different countries has demonstrated that oxalic acid from food plays an insignificant role in the formation of kidney stones.
Excesses in Animal Protein are a Major Risk Factors in Kidney Stones Formation. You may read the rest of this article on my blog.
4. Claim: Fruits are too sweet for you
I completely understand how eating only unripe, conventionally grown fruit might be considered to be harmful to health. Some of you might wonder, what can I do if I don’t have access to high quality fruit? First of all, become aware. Second, go to U-pick farms in the summer and freeze berries and fruit for your winter. Third, talk to your local farmers and see if they can help you find a way to provide you with organic produce. Finally, watch Valya’s presentation on Espalier and harvest your own perfect fruit.
It is my opinion that fruit, if it’s ripe and organic, is an essential part of the human diet. Even in Northern Siberia, where there is a permanent frost, people gather both sweet and sour berries in the summer. However I don’t recommend a completely fruitarian diet because it is not complete. Greens are the most nutritious food on our planet. In my food pyramid greens take the first place and ripe organic fruit takes the second. You may read the rest of this article on my blog.
Everyone should eat more greens. By consuming green smoothies, my body is able to absorb up to two bunches (two pounds) of greens every day. That is why I choose to encourage people to consume green smoothies.
If alternative doctors will fight with each other over non-essential particulars of natural healing, we may only confuse people. Moreover, we may become easy prey for the medical establishment’s criticism. Instead, let us unite on whatever common grounds we share.”
(2) Effect of bran particle size on gastric emptying and small bowel transit in humans: a scintigraphic study R Vincent, A Roberts, M Frier, A C Perkins, I A MacDonald, R C Spiller. Gut 1995; 37: 216-219
(3) Uckoo RM, et al “Grapefruit phytochemicals composition is modulated by household processing techniques.”.Journal of Food Science Texas, USA; 2012 Sep;77(9):C921-6.
Megan Sheppard is an aficionado of all things plant-based, particularly if it involves herbs and tastes delicious! She works as a Herbalist specialising in nutrition, and works freelance as a natural health author and advisor. Megan’s herbalicious creations can be found at Wildflower Botanicals, a garden of organic and ethically sourced teas, chocolate, and other delights!