As natural sugar is high in calories and a high intake can lead to weight gain, many people switch to artificial sweeteners, which are made from synthetic chemicals that give a sweet taste without the calories. As artificial sweeteners are 200 times or more sweeter than sugar, much less is required to sweeten food and soft drinks. While artificial sweeteners can lower blood sugar levels and may help with weight loss in the short term, research has indicated that a high intake of artificial sweeteners over the longer term may confuse your body into storing fat and inducing diabetes.
Artificial sweeteners can affect the chemistry in the body:
Artificial sweeteners used in moderation may not harm the body, while research has linked a high intake of artificial sweeteners to various adverse health conditions, such as weight gain, metabolic syndrome, Type 2 diabetes, hypertension, and vascular disease. These health conditions may result from the differences in the way sugar and artificial sweeteners are processed in the body.
- Brain activation: Glucose is a simple sugar, naturally occurring in sugar and carbohydrates. Glucose is an important source of energy for every cell in the human body. The brain, being rich in neurons (nerve cells), is a very energy demanding organ and uses half of all the glucose derived energy in the body. Sugar also affects the way our brains work, by increasing the electrical activity in certain parts of the brain, which means these parts become “excited”, a condition called brain activation. Both artificial sweeteners and sugar activate the primary taste pathway, though the glucose in sugar elicits a significant response from several regions of the taste-reward system in the brain.
- Reward pathway: When eating something sweet, the brain releases dopamine, which triggers the brain’s reward center. The reward pathway in the brain consists of a series of connections that deliver neurotransmitters such as dopamine, which makes us feel good. The first mouthful of sugar activates the taste receptors on the tongue and sends a signal to the cerebral cortex in the brain, which then signals the brain’s pleasure and reward center (limbic region), basically asking do you like it or not? The reward center confirms and asks for more of the same. The brain then spikes the release of the neurotransmitter dopamine, which makes you experience feelings of pleasure. Over the long term, daily sugar overdoses can lead to cravings and increased tolerance to sugar – meaning you need more to get the same feelings of pleasure. Artificial sweeteners also activate reward pathways, as they provide the pleasure from being sweet, but the pleasure pathway does not get deactivated, since the expected calories do not arrive, which may result in carb cravings. Experiencing less pleasure in the brain from the consumption of artificial sweeteners can result in overeating other foods with a high calorie count to feel satisfied, compared to eating real sugar.
- Brain tolerance to sweetness: Sweetness in food or beverages increases the brain’s tolerance for sweetness, meaning the more you eat sweet things, the more you need to eat in future for the brain to recognize something as being sweet. This can lead to cravings for more sugar and calories. When the brain becomes tolerant to sweetness, it can result in overeating.
- Sugar receptors: Overstimulation of sugar receptors from the intense sweetness of artificial sweeteners can lead to people finding less intense sweetness in food such as fruit less appealing, or they may even find vegetables downright unpalatable, says Harvard.
- Blood sugar levels: Blood sugar levels increase when we eat food containing sugar or carbohydrates, which gets absorbed into the bloodstream during digestion. When blood sugar levels rise, the pancreas secretes the hormone insulin, which regulates blood sugar levels and bring blood sugar levels back to normal. Insulin acts like a key that unlocks blood sugar to leave the blood and enter cells in the body, where it is used as a source of energy. Unlike real sugar, most artificial sweeteners do not increase blood sugar levels and do not trigger insulin production. However, the sight, taste, and smell of food can trigger the release of small amounts of insulin, even before eating and before any sugar gets digested or enters the bloodstream. This response is referred to as cephalic phase insulin release. The sweet taste of artificial sweeteners can trigger the release of cephalic phase insulin, which may disturb metabolism, as the brief spike in insulin secretion is not accompanied by a rise in blood sugar levels.
- Needing more calories: As artificial sweeteners do not provide the calories and glucose the body needs, and the usual insulin production is not activated, it can lead to consuming larger quantities of food to satisfy the need for calories. Even if there are enough calories in one’s diet, artificial sweeteners can trick the body into thinking it needs more calories from more food.
- Gut bacteria: As the microorganisms in the digestive system (called the gut microbiota), which helps to break down food, reacts differently to artificial sweeteners than to sugar, it affects digestion. Studies have found that these microorganisms become less able to break down real sugars, the longer they are exposed to artificial sweeteners. Disruption of the intestinal microbiota may not only affect the amount of nutrients that the body can extract from food, as it can also increase the risk for both obesity and diabetes.
- Genetic effects: Artificial sweeteners have been linked to metabolic changes at the genetic level in the body, such as altering the expression of certain genes that are responsible for lipid (fat) metabolism in the cells of the body. Scientists have seen an increase in lipids in the bloodstream, coupled with a decrease in a biomolecule that is involved in the clearing of lipids from the bloodstream. While normal sugar can contribute to heart disease through insulin resistance and by damaging the cells that line the body’s blood vessels, it appears as if artificial sweeteners may contribute to metabolic disorders by changing the activity of certain genes involved with the breakdown of fats and proteins.
Effects of artificial sweeteners on your health
The way artificial sweeteners may affect certain chemical processes in the body have been linked to certain health conditions. It should be kept in mind that health-related research reflects significant tendencies found in the studies, which does not necessarily mean that all of us would be affected in the same way. We are not created equal and have different genes, lifestyles, and eating habits.
The extensive use of artificial sweeteners has been linked to health conditions such as:
- Glucose intolerance: Changes to the gut microbiota due to regular use of artificial sweeteners have been linked to impaired glucose tolerance. Glucose intolerance, a condition also known as prediabetes, can raise blood sugar levels and increase the risk for diabetes. It has also been linked to gut dysbiosis, which is associated with irritable bowel syndrome and a decreased ability to absorb all the nutrients from our food.
- Metabolism: Artificial sweeteners have been found to interfere with the body’s metabolism and the way food is converted into energy or stored as fuel. When tasting something sweet, our bodies instinctively react by releasing hormones to activate the body’s metabolism in preparation for sugar. When the body receives the sweetness from artificial sweeteners without any of the energy providing glucose or calories, the body may stop activating our metabolism. This means that when food with calories is consumed, the body may not be well-prepared to metabolize the calories, potentially leading to higher blood sugar levels and weight gain.
- Metabolic syndrome: A high consumption of artificial sweeteners may lead to a higher risk of metabolic syndrome – which describes a cluster of conditions such as increased blood pressure, high blood sugar levels, abnormal cholesterol levels, and excess body fat around the waist – all of which can increase the risk of stroke, hypertension, and heart disease.
Types of artificial sweeteners:
The Food and Drug Administration (USA) has approved just five artificial sweeteners for use in the United States, namely saccharin, acesulfame potassium, aspartame, neotame, and sucralose, as well as one natural sweetener, namely stevia. Stevia is not manufactured like artificial sweeteners, as it is derived from the stevia brush plant that is native to Central and South America and contains no carbohydrates or calories.
While artificial sweeteners are the main type of sugar substitutes, a smaller number of sweeteners are made from sugar alcohols. Unlike the name implies, sugar alcohols are non-alcoholic, as they do not contain the ethanol that is found in alcoholic drinks. Sugar alcohol is found naturally in certain fruit and vegetables. The sweeteners made from sugar alcohol are less sweet than artificial sweeteners, and with about 50% less calories than sugar, is widely used in the food industry as thickeners and sweeteners.
Sugar alcohols are carbohydrates and can raise blood sugar levels. The most common types of sugar alcohols are erythritol, lactitol, maltitol, mannitol, sorbitol, and xylitol.
Sugar alcohols are absorbed at 50% of the rate of sugars, resulting in less of an effect on blood sugar levels when compared to sucrose, as measured on the glycemic index. When consumed in large amounts, sugar alcohols may cause gastro-intestinal disturbances, such as bloating, osmotic diarrhea, and flatulence.
Adding together the various mechanisms of potential harm from artificial sweeteners – from confusing the body with the sweet taste without calories, to altering the gut bacteria – artificial sweeteners have likely played a role in worsening the widespread obesity and diabetes epidemics, says Dr. Mercola.
If you consume sugar in limited quantities, you may as well stick to natural sugar. Artificial sweeteners in moderation can be a useful option for people with diabetes or to help with weight management. The frequent and high levels of consumption of artificial sweeteners, however, may be harmful to your health, as it is hidden in many processed foods and in other products such as soft drinks and candy.
The best option may well be to gradually lessen the overall consumption of sugar or artificial sweeteners, which can retrain your palate over time and reduce the cravings for sweetened foods and beverages.
Artificial sweeteners are not necessarily the magic bullets for weight control they are claimed to be.
What is worse for you: sugar or artificial sweeteners? Published 15 January 2018. Cleveland Clinic. (www.clevelandclinic.org)
Trick or treat? How artificial sweeteners artificial sweeteners affect the brain and body. Published 29 March 2019. Frontiers. (Frontiers is an open access publisher and open science platform.) (www.frontiersin.org)
4 Dangerous effects of artificial sweeteners on your health. Published 10 July 2013. Medical Daily. (www.medicaldaily.com)
Artificial sweeteners: sugar-free, but at what cost? Published online and updated 8 January 2018. Harvard Medical School. (www.health.harvard.edu)
Artificial sweeteners may change our gut bacteria in dangerous ways. Published 1 April 2015. Scientific American. (www.scientificamerical.com)
What do artificial sweeteners do to your body? Published 8 December 2017. Eating Well. (www.eaitingwell.com)
Artificial sweeteners: Where do we stand? Published 23 April 2018. CNN Health. (www.cnn.com)
How artificial sweeteners may raise your risk of diabetes and obesity. Published 8 May 2018. Mercola. (www.mercola.com)