Insulin resistance: a condition that can affect us all
Before explaining what insulin resistance (IR) is, it’s important to know what insulin is and what its function is in our body. Insulin is a hormone that is released in the pancreas, after a diet rich in sugars or starches (carbohydrates); its function in the body is to allow its entry into cells or organs so that they can transform it into energy (1). To understand how the process of insulin resistance is generated, the body goes through a series of steps or metabolic pathways to try to compensate for the high level of blood sugar (this happens when there is overeating throughout the day or well meals very rich in sugars and poorly balanced).
In a first step, the sugars that enter our body stimulate the release of insulin by the pancreas. This hormone will be responsible for storing them in the form of glycogen in the liver and muscle; according to some studies approximately between 70% and 90% of the sugars from our diet are stored in this way (2). Once the different deposits of our body are full, they prevent more sugars from entering, leaving them free in the blood; this makes the pancreas continue to release more insulin. The second step is that, not being able to store more the sugars from our diet, the liver converts glucose into triglycerides and sends them to adipose tissue to be stored in the form of localized and visceral fat (3). A colloquial way to understand this is to try to fill a bottle with water when it is already full, in the end the water overflows over the edges making it spill.
Every time a poorly balanced diet is ingested or at night; foods rich in sugars from fruits, flours and ultra-processed foods, will stimulate the release of insulin. If the diet is not controlled, it will remain high in a sustained way, which is known as hyperinsulinemia and leads to a greater sensitivity of our body towards these groups of foods, which translates into a sharp increase in weight.
It is important to bear in mind that there are moments or physiological conditions that trigger a sharp rise in insulin (hyperinsulinemia) such as emotional stress, inflammatory processes in response to a sudden illness or a hidden infection. Therefore, hyperinsulinemia is considered a response to a stimulus that is producing hormonal imbalances in our body and that can be reversible (6).
While, when the organs and cells no longer respond to the action of insulin (insulin resistance) it becomes an irreversible and asymptomatic disease that can go unnoticed for many years. Its long-term consequences are the increase in blood sugar, and with this the risk of triggering metabolic diseases (excess weight, diabetes, metabolic syndrome, coronary disease) (4).
The cause of the disease of insulin resistance is the result of several factors among them is age, sex, genetic predisposition, physical activity, lifestyles and unbalanced diet. It is possible that the person notices that their body has a high sensitivity towards certain groups of foods that generate sharp increases in weight and increase in abdominal fat. So the only manifestation that we can find when the blood sugar has been high for many years is the damage in all the organs and systems of the body (7).
Despite the fact that some people may be genetically more prone to develop insulin resistance, perhaps the greatest impact has been the change in our food environment in recent decades. There is greater availability of ultra-processed meals and drinks that are easily accessible, which represent an affordable value for the consumer. This may have led entire populations to adopt an unhealthy lifestyle, characterized by the consumption of high levels of sugar, starches and other refined carbohydrates (8).
According to Herpen & Schrauwen (2017) and Ros & Medina (2011) insulin resistance is related to excess weight (overweight-obesity), with prediabetes, type 2 diabetes, polycystic ovary syndrome (PCOS), cardiovascular diseases and other metabolic conditions, such as hypertension and non-alcoholic fatty liver. Therefore, lifestyle, eating habits and physical activity are important factors that can maintain, increase or decrease the risk of IR.
To control insulin resistance, it is necessary to balance the diet with an increase in the consumption of vegetables and proteins, reducing processed sugars, and flours. This, along with patterns of healthy habits such as: maintaining a schedule in meals, avoiding snacks and copious meals at night along with cycles of cardiovascular activity, treating sleep problems and stress improve the hormonal environment making the body improve insulin sensitivity and allow its long-term control (9,10).
In summary, it is necessary for the changes in the patient’s lifestyle to be carried out in a sustained and indefinite way that allows them to maintain a balanced diet in all food groups, so that in this way the hormonal environment is controlled, and allows them to maintain good metabolic functioning which will translate into better weight control.
References:
- Barazzoni, R., Gortan Cappellari, G., Ragni, M. et al. Insulin resistance in obesity: an overview of fundamental alterations. Eat Weight Disord 23, 149ā157 (2018). https://doi.org/10.1007/s40519-018-0481-6
- VictĆ²ria Ceperuelo-MallafrĆ©, Miriam Ejarque, Carolina Serena, Xavier Duran, Marta Montori-Grau, Miguel Angel RodrĆguez, Oscar Yanes, Catalina NĆŗƱez-Roa, Kelly Roche, Prasanth Puthanveetil, Lourdes Garrido-SĆ”nchez, Enrique Saez, Francisco J. Tinahones, Pablo M. Garcia-Roves, Anna M GĆ³mez-Foix, Alan R. Saltiel, Joan Vendrell, Sonia FernĆ”ndez-Veledo, Adipose tissue glycogen accumulation is associated with obesity-linked inflammation in humans, Molecular Metabolism, Volume 5, Issue 1, 2016, Pages 5-18, ISSN 2212-8778, https://doi.org/10.1016/j.molmet.2015.10.001.
- Ros PĆ©rez M, Medina-GĆ³mez G. Obesity, adipogenesis and insulin resistance. Endocrinol Nutr. 2011 Aug-Sep;58(7):360-9. Spanish. doi: 10.1016/j.endonu.2011.05.008. Epub 2011 Jul 22. PMID: 21778123.
- Matulewicz, Natalia & Karczewska-Kupczewska, Monika. (2016). Insulin resistance and chronic inflammation. Postepy higieny i medycyny doswiadczalnej (Online). 70. 1245-1258. 10.5604/01.3001.0009.6902.
- Varman T. Samuel, Gerald I. Shulman, The pathogenesis of insulin resistance: integrating signaling pathways and substrate flux. J Clin Invest. 2016;126(1):12-22. https://doi.org/10.1172/JCI77812.
- A. van Herpen, V.B. Schrauwen-Hinderling, Lipid accumulation in non-adipose tissue and lipotoxicity, Physiology & Behavior, Volume 94, Issue 2, 2008, Pages 231-241, ISSN 0031-9384, https://doi.org/10.1016/j.physbeh.2007.11.049.
- Irimia JM, Meyer CM, Segvich DM, Surendran S, DePaoli-Roach AA, Morral N, Roach PJ. Lack of liver glycogen causes hepatic insulin resistance and steatosis in mice. J Biol Chem. 2017 Jun 23;292(25):10455-10464. doi: 10.1074/jbc.M117.786525. Epub 2017 May 8. PMID: 28483921; PMCID: PMC5481557.
- GoÅÄ bek K, Regulska-Ilow B. Dietary support in insulin resistance: An overview of current scientific reports. Adv Clin Exp Med. 2019;28(11):1577ā1585. doi:10.17219/acem/109976
- Jensen JĆørgen, Rustad Per, Kolnes Anders, Lai Yu-Chiang, The Role of Skeletal Muscle Glycogen Breakdown for Regulation of Insulin Sensitivity by Exercise, Frontiers in Physiology, Volume 2, 2011. DOI=10.3389/fphys.2011.00112
- Alexander Sakers, Mirian Krystel De Siqueira, Patrick Seale, Claudio J. Villanueva, Adipose-tissue plasticity in health and disease, Cell, Volume 185, Issue 3, 2022, Pages 419-446, ISSN 0092-8674, https://doi.org/10.1016/j.cell.2021.12.016.
Author: Catherine Del Pilar Villoria Rojas
Medical Director, Natural Body Center. Medical Researcher University Complutense of Madrid.
