The Problem With Smoothies
Whether it is on Facebook, Instagram, Pinterest or in health magazines, smoothies seem to be the cornerstone of a new health cult – drink your nutrients. Smoothies can be green, pink, or even brown, and they can contain fruit and vegetables, leaves and spices, as well as protein powders, nuts and seeds. They are supposed to provide the answer to everyone's rushed mornings, and help those looking for weight loss to effortlessly lose weight. They are also known as super anti-aging foods which will boost our immunity and even make our skin glow. Maybe it is time to look at them in perspective, and separate the reality from the hype.
Maybe smoothies are too smooth?
When smoothies are completely smooth and require no chewing, people don't chew them. They swallow them like a thick milkshake. No chewing means that no digestive enzymes are released in the mouth, which is where digestion starts. The result is that when the thick, nutrient-rich smoothie arrives in your stomach, it has a harder time being digested and then absorbed.
The solution – if you love the creamy texture, then remember to "chew" the mixture, as if it was food with texture and crunch. A tasty, and easy-to-remember solution, is to add a "crunch factor", like whole nuts and seeds, to your smoothie just before you eat it. This forces you to chew your smoothie, adding nutrients as well as enzymes to your nutrient-rich meal. Two added bonuses are that your teeth get a ‘workout, helping to keep them strong and healthy, and your brain gets stimulated via the activity in your jaw muscles.
Maybe smoothies are too sweet?
It is challenging to eat a smoothie when it is not sweet. It can easily taste like cold soup, which is not very appealing to most people first thing in the morning. So, fruit is added, often in greater quantities than what you could peel and chew with ease. This leads to an overconsumption of sweet fruit, which is not a great start to the day. Instead of setting the stage for blood glucose stability, you may be heading for a big sugar-slump later in the morning. In addition, fruit juice is the foundation of many smoothies, making them once again too sweet, without even the added fibre that real fruit can provide.
The solution is to use coconut water, milk, or almond milk as the foundation of the smoothie, and cut down on the overly sweet fruit. You could also substitute berries or a small frozen banana or a date for sweetness.
Maybe smoothies help you gain weight?
When you eat quickly, either not chewing your food properly, or swallowing smoothies that do not need chewing, the hormone leptin does not have time to get to the hypothalamus in the brain, to tell it that you are getting full. It takes about 20 minutes for the brain to register satiation after you start eating, so you may not realize that you are full until quite a while after you have eaten your smoothie. This can lead to you eating more food than you need after your smoothie.
The solution is to add a "crunch factor", which will force you to chew your smoothie, naturally taking more time to eat it, by which time your hypothalamus will register satiation.
In conclusion, enjoy your smoothies, but be aware that they can't replace all your meals. And add the "crunch factor" to your breakfast smoothies to stimulate your digestive juices and to make sure that your brain gets the satiation signal that it needs.
Andrade AM, et al. Eating slowly led to decreases in energy intake within meals in healthy women. J Am Diet Assoc. 2008 Jul;108(7):1186-91.
Brennan CS. Dietary fibre, glycaemic response, and diabetes. Mol Nutr Food Res. 2005 Jun; 49(6): 560-70.
Hirano Y, et al. Effects of chewing in working memory processing. Neurosci Lett. 2008 May;436(2);189-92.
Karl JP, et al. Independent and combined effects of eating rate and energy density on energy intake, appetite, and gut hormones. Obesity (Silver Spring). 2013 Mar;2193):E244-52.
Kim MK, Park JH. Conference on "Multidisciplinary approaches to nutritional problems". Symposium on "Nutrition and health". Cruciferous vegetable intake and the risk of human cancer: epidemiological evidence. Proc Nutr Soc. Feb 2009; 68(1): 103-10.
Rajendran N, et al. Role of diet in the management of inflammatory bowel disease. World J Gastroenterol. 2010 March 28; 16(12): 1442-1448.