Glucose

Glucose is a type of sugar that provides energy for your body. It’s one of the main sources of fuel your body uses to keep you moving, thinking and functioning properly. Every cell in your body needs glucose to work effectively.

What is glucose?

Glucose is a simple sugar, also known as a monosaccharide [1]. It naturally occurs in many foods, especially those that contain carbohydrates such as fruits, vegetables, bread and pasta. Once eaten, your body breaks down carbohydrates into glucose [2], which enters your bloodstream.

How does glucose work in the body?

When you eat, your body digests food and releases glucose into the blood. The hormone insulin, made by your pancreas, helps move glucose from your blood into your cells [3], where it’s used for energy. Any extra glucose that isn’t needed right away is stored in your liver and muscles for later use [4].

Why is it important to monitor your blood glucose levels?

Keeping your blood glucose levels balanced is important. If your levels are too low (hypoglycaemia) [5] or too high (hyperglycaemia) [6], it can cause health problems. Consistently high glucose levels over time are linked to diabetes and other metabolic conditions [7][8].

Why does glucose matter in your body?

Glucose is essential because it fuels your brain and body.

• Your brain relies heavily on glucose for energy [9][10], which is why you might feel tired or dizzy if your blood sugar drops too low.
• It also supports muscle activity [11][12], helping you stay active throughout the day.

How does glucose affect your health?	Description
Regulates energy production [2]	Glucose provides energy to the brain, muscles, and other tissues, supporting physical activity and mental clarity.
Influences blood sugar balance [13]	Proper regulation of glucose levels helps prevent hyperglycemia (high blood sugar) and hypoglycemia (low blood sugar), both of which can have harmful effects on health.
Supports metabolic health [14]	Glucose metabolism affects fat storage and muscle mass, influencing overall weight and body composition.
Affects insulin sensitivity [15][16]	Chronic high glucose levels can lead to insulin resistance, increasing the risk of type 2 diabetes and metabolic syndrome.

Balanced glucose levels are essential for energy production, metabolic health, and disease prevention, particularly for conditions like diabetes and obesity.

Maintaining a healthy balance of glucose is key to good health

Maintaining a healthy balance of glucose is key for good health. Eating a balanced diet that includes complex carbohydrates, fibre and protein can help keep blood sugar levels steady [17]. Regular exercise also helps your body use glucose more effectively [18][19][20].

If you have diabetes or another condition that affects your blood sugar, it’s important to monitor your glucose levels and follow medical advice on diet, exercise and medication.

What are the best natural sources of glucose?

Foods that contain carbohydrates are the main sources of glucose [21][22]. These include:

• Whole grains like oats, rice and bread
• Fruits such as apples, bananas and grapes
• Vegetables, especially root vegetables like potatoes and carrots
• Dairy products such as milk and yoghurt
• Sweet foods and drinks, including table sugar and sweets

Learn more about the best foods for diabetes on our blog.

Nutritionist's Corner: Final Thoughts

“Glucose is your body’s main source of energy, and it plays a vital role in both brain and muscle function. The key is balance, choosing nutritious sources of carbohydrates and avoiding excessive added sugars helps maintain steady energy and long-term health.”
- Yusra Serdaroglu Aydin, MSc RD

Sources

[1] Holesh JE, Aslam S, Martin A. Physiology, Carbohydrates. [Updated 2023 May 12]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK459280/

[2] Nakrani MN, Wineland RH, Anjum F. Physiology, Glucose Metabolism. [Updated 2023 Jul 17]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK560599/

[3] Rahman MS, Hossain KS, Das S, Kundu S, Adegoke EO, Rahman MA, Hannan MA, Uddin MJ, Pang MG. Role of Insulin in Health and Disease: An Update. Int J Mol Sci. 2021 Jun 15;22(12):6403. doi: 10.3390/ijms22126403. PMID: 34203830; PMCID: PMC8232639.

[4] Patino SC, Orrick JA. Biochemistry - Glycogenolysis. [Updated 2024 Jan 27]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK549820/

[5] Low blood sugar (hypoglycaemia) - NHS

[6] High blood sugar (hyperglycaemia) - NHS

[7] Mouri MI, Badireddy M. Hyperglycemia. [Updated 2023 Apr 24]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK430900/

[8] Key cause of type 2 diabetes uncovered - University of Oxford

[9] Ritter S. Monitoring and Maintenance of Brain Glucose Supply: Importance of Hindbrain Catecholamine Neurons in This Multifaceted Task. In: Harris RBS, editor. Appetite and Food Intake: Central Control. 2nd edition. Boca Raton (FL): CRC Press/Taylor & Francis; 2017. Chapter 9. Available from: https://www.ncbi.nlm.nih.gov/books/NBK453140/ doi: 10.1201/9781315120171-9

[10] Sugar and the Brain - Harvard Medical School

[11] Use of glucose for energy production in muscle cells from patients with ME/CFS - ME Research UK

[12] Peinado AB, Rojo-Tirado MA, Benito PJ. El azúcar y el ejercicio físico: su importancia en los deportistas [Sugar and exercise: its importance in athletes]. Nutr Hosp. 2013 Jul;28 Suppl 4:48-56. Spanish. doi: 10.3305/nh.2013.28.sup4.6796. PMID: 23834092.

[13] Wolever TM, Miller JB. Sugars and blood glucose control. Am J Clin Nutr. 1995 Jul;62(1 Suppl):212S-221S; discussion 221S-227S. doi: 10.1093/ajcn/62.1.212S. PMID: 7598079.

[14] Alam YH, Kim R, Jang C. Metabolism and Health Impacts of Dietary Sugars. J Lipid Atheroscler. 2022 Jan;11(1):20-38. doi: 10.12997/jla.2022.11.1.20. Epub 2022 Jan 17. PMID: 35118020; PMCID: PMC8792817.

[15] Mingrone G, Panunzi S, De Gaetano A, Ahlin S, Spuntarelli V, Bondia-Pons I, Barbieri C, Capristo E, Gastaldelli A, Nolan JJ. Insulin sensitivity depends on the route of glucose administration. Diabetologia. 2020 Jul;63(7):1382-1395. doi: 10.1007/s00125-020-05157-w. Epub 2020 May 8. PMID: 32385603; PMCID: PMC7286868.

[16] Li, M., Chi, X., Wang, Y. et al. Trends in insulin resistance: insights into mechanisms and therapeutic strategy. Sig Transduct Target Ther 7, 216 (2022). https://doi.org/10.1038/s41392-022-01073-0

[17] Diabetes diet: a healthy, balanced diet for diabetes - Diabetes UK

[18] Kanaley JA, Colberg SR, Corcoran MH, Malin SK, Rodriguez NR, Crespo CJ, Kirwan JP, Zierath JR. Exercise/Physical Activity in Individuals with Type 2 Diabetes: A Consensus Statement from the American College of Sports Medicine. Med Sci Sports Exerc. 2022 Feb 1;54(2):353-368. doi: 10.1249/MSS.0000000000002800. PMID: 35029593; PMCID: PMC8802999.

[19] Schneider SH, Amorosa LF, Khachadurian AK, Ruderman NB. Studies on the mechanism of improved glucose control during regular exercise in type 2 (non-insulin-dependent) diabetes. Diabetologia. 1984 May;26(5):355-60. doi: 10.1007/BF00266036. PMID: 6376244.

[20] Diabetes Insulin and exercise - Milton Keynes University Hospital NHS Foundation Trust

[21] Carbohydrates and diabetes: What you need to know - Diabetes UK

[22] Carbohydrate Reference Table - Diabetes Smart