Considering Keto? How This “Evolutionary” Way of Eating May Change Your Life

Amy Gutman, MD, FACEP, a distinguished attending emergency physician at Advent Health in Orlando, Florida, earned her Doctor of Medicine degree from Saba University School of Medicine in 2002. Following her medical education, Dr. Gutman completed her surgical residency at Bassett Medical Center in New York and her emergency... more
A ketogenic diet, commonly called a "keto diet," is a high-fat, low-carbohydrate eating plan that is the opposite of how most people eat—the "standard American diet," known as the "SAD" diet. By restricting carbohydrate intake, a ketogenic diet forces your body to burn fat for energy instead of glucose, leading to a metabolic state called "ketosis."
This diet aims to achieve ketosis, in which the body starts burning fat for energy instead of glucose from carbohydrates. To achieve this, you must consume most of your calories from fat, a moderate amount from protein, and a minimal amount from carbohydrates.
Wait! Don't turn the page! Yes, this goes against conventional "diet" advice. Still, the keto diet is anything but unconventional—in fact, it has been used clinically to treat neurologic diseases successfully since at least 461 BCE! 1 Hippocrates was ahead of his time when he stated, "Let food be thy medicine, and medicine thy food." A large and growing body of scientific studies shows that changing your diet can improve and even cure systemic chronic illnesses7-8!
The keto diet changes the way your body uses food; by doing so, it significantly decreases cellular inflammation. As cellular inflammation is the cause of most chronic illnesses, like cardiovascular, kidney, neurological, psychiatric, autoimmune, rheumatologic, and oncologic diseases, this diet naturally decreases your risk of developing these life-altering illnesses2-5. Even more importantly, if the keto diet is adopted, if you have a chronic disease, they tend to improve rapidly6.
So, how does a ketogenic diet decrease inflammation? Typically, dietary carbohydrates provide most of the fuel your body needs. Unfortunately, most people overeat carbohydrates, leading to excess glucose in the blood. The pancreas must produce more and more insulin to convert this glucose into energy. The pancreas becomes overworked, leading to "insulin resistance." Over time, the amount of glucose in the blood rises, leading to type 2 diabetes and whole-body inflammation. This inflammatory state is what directly causes heart attacks, strokes, high blood pressure (hypertension), and kidney and vascular disease. It also contributes to neurological diseases, autoimmune diseases, rheumatological diseases, and poor gut health – every body system is involved9.
The keto diet reduces the number of carbs you eat and the glucose in your system. It teaches your body to burn fat for fuel instead, naturally decreasing your circulating glucose and insulin resistance. The result is reduced inflammation, increased gut health, and decreased chronic diseases fueled by inflammation. Are there health benefits to some nutrient-rich foods with higher levels of carbohydrates? Yes, which is why lower carbohydrate fruit and vegetables are included in a keto diet. Generally, though, most carbohydrates are restricted to help naturally lower glucose levels.
The standard American diet consists of 30% fats, 15% proteins, and 55% carbohydrates, often ultra-processed and filled with artificial chemicals. The standard keto diet ideally consists of whole, minimally processed foods, 70-80% fats, 10-20% proteins, and 5-10% carbohydrates (less than 50 grams) daily10.
Standard American Diet (“SAD”) vs Ketogenic Diet Macronutrients
There are many food options on a high-fat, low-carbohydrate diet:
Foods to be avoided or strictly limited "Non-Keto" or High-Carbohydrate Foods:
To achieve ketosis, most people must consume less than 50 grams of carbohydrates daily. That's about 2-3 slices of bread, two bananas, a large ear of corn, ½ cub of chickpeas, or 1 cup of pasta each. If you keep under 50 grams of carbohydrates daily, most people enter ketosis in 3-5 days. Some report the "keto flu11" – feeling worn out, tired, fatigued, and achy. This is an expected state as your body goes from using glucose to ketones for energy, and the body exhausts its glucose stores. A minority of patients may also have "keto" breath and constipation – the two most common side effects that are easily remedied with fat, fiber, and protein modifications12.
But what about high cholesterol? A concern from many is the effect on cholesterol levels; after all, if you are eating more fat, you are eating more cholesterol. As it turns out, the latest research into cholesterol and LDL cholesterol shows that earlier studies have overestimated the harmful effects of cholesterol13-15. Think about it: cholesterol is present in every cell wall of your body. Every nerve in your body is coated in cholesterol like an electrical cable that helps it activate. Breastmilk is full of cholesterol as it helps babies' brains and bodies grow; indeed, something essential for healthy cell growth in a newborn is not toxic in adults!
Adding intermittent fasting intervals will help you enter ketosis faster. Intermittent fasting is a very evolutionary way of eating16. Our evolutionary ancestors had "feast or famine" periods related to successful animal protein hunts. Our bodies naturally remember this state and use time without food to help repair damaged cells, which also helps with overall health.
In addition to the positive impact on chronic disease, ketosis has many health benefits, one of the greatest being weight loss. Because ketogenic foods are high in fat, protein, and essential nutrients, these foods naturally make you feel more satisfied or "high satiety." In a short period, you start eating less. Your hunger is controlled because all your food fulfills your dietary needs. You don't snack on ultra-processed, pro-inflammatory processed snacks because you aren't hungry. You lose abdominal or "visceral" fat while maintaining a lean mass.
It's crucial to understand how metabolic health ties into overall well-being. For example, there is a significant link between metabolic health and mental health. A striking statistic is that over 80% of people with Alzheimer's had a diagnosis of diabetes before the onset of dementia17. Many scientists believe diabetes itself is a risk factor marker for developing dementia. The link is so well documented that Alzheimer's is also known as "Type 3 Diabetes”18.
This connection hints at how poor metabolic health can affect our brain's functioning. Increased inflammation and insulin resistance accelerate brain aging, contributing to conditions like Alzheimer's dementia. A constant state of poor metabolic health, elevated glucose, and inflammation is linked directly to the development of cardiovascular disease, kidney failure, liver disease, and cancer. Yes – that donut you had for breakfast can cause a heart attack, put you on dialysis, and give you cancers of literally every organ system. Why? If your body is experiencing inflammation, which in many cases is caused by "hyperinsulinemia,"
Let's break this down: when you eat a constantly high sugar-based (i.e., carbohydrate) diet, your pancreas must continually produce high insulin levels. Over time, that stresses out the pancreatic cells and their mitochondria. Your body then starts to become "resistant" to that insulin, so even high insulin levels do not fully metabolize your circulating glucose in the bloodstream. If your glucose is not metabolized, your body, despite having a ton of sugar in your blood, still thinks it is "hungry" and needs fuel. So, you eat another high carbohydrate meal, which again pokes at the pancreas to put out more and more insulin, which causes more and more body insulin resistance. At some point, your body can't use insulin at all, so you end up with both high levels of toxic glucose/sugar and high levels of non-functional insulin. That is how type 2 diabetes develops.
Think of glucose as an inflammatory substance – you put a penny in a bottle of soda, and it starts to rust and dissolve, right? Well, picture that same thing happening in every vessel of your body. No wonder this constant inflammatory state induces strokes, heart attacks, rashes, dementia, and autoimmune diseases.
So, what can we do about it? Focus on fundamental practices for maintaining good metabolic health. Eating a balanced diet rich in whole foods, avoiding processed snacks, and staying physically active keeps inflammation low and our bodies function well.
Although it is simple, it's not easy! As with any change in your lifestyle, having the right support system is key. Find a nutritionist or dietician who specializes in ketogenic diets to support. Increasing numbers of "traditional" internal medicine, family practitioners, and functional medicine clinicians are integrating ketogenics into their medical practices. Work with your support team, and within a short period, you will likely be able to wean down or potentially off your chronic medications – but never stop a medication without your physician's input!
Let food be your medicine, and consider a ketogenic diet to start on your path to a long, healthy life, conquering chronic disease along your wellness pathway.
Citations
- Wheless, J.W. (2004). History and Origin of the Ketogenic Diet. In: Stafstrom, C.E., Rho, J.M. (eds) Epilepsy and the Ketogenic Diet. Nutrition and Health. Humana Press, Totowa, NJ. https://doi.org/10.1007/978-1-59259-808-3_2.
- Janson J, Laedtke T, Parisi JE, O’Brien P, Petersen RC, Butler PC. Increased risk of type 2 diabetes in Alzheimer disease. Diabetes. 2004; 53:474–481.
- De la Monte, S. M. (2017). The role of insulin resistance in the neurodegenerative processes of Alzheimer's disease. Experimental Neurology, 298(Pt B), 42-58. https://doi.org/10.1016/j.expneurol.2017.09.003.
- Zarrin AA, Monteiro RC. Editorial: The Role of Inhibitory Receptors in Inflammation and Cancer. Front Immunol. 2020 Dec 22;11:633686. doi: 10.3389/fimmu.2020.633686. PMID: 33414792; PMCID: PMC7783443.
- Liu J, Ting JP, Al-Azzam S, Ding Y, Afshar S. Therapeutic Advances in Diabetes, Autoimmune, and Neurological Diseases. Int J Mol Sci. 2021 Mar 10;22(6):2805. doi: 10.3390/ijms22062805. PMID: 33802091; PMCID: PMC8001105.
- Kianmehr H, Zhang P, Luo J, et al. Potential Gains in Life Expectancy Associated With Achieving Treatment Goals in US Adults With Type 2 Diabetes. JAMA Netw Open. 2022;5(4):e227705. doi:10.1001/jamanetworkopen.2022.7705.
- Masood W, Annamaraju P, Khan Suheb MZ, Uppaluri KR. Ketogenic Diet. 2023 Jun 16. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan–. PMID: 29763005.
- Baylie T, Ayelgn T, Tiruneh M, Tesfa KH. Effect of Ketogenic Diet on Obesity and Other Metabolic Disorders: Narrative Review. Diabetes Metab Syndr Obes. 2024 Mar 21;17:1391-1401. doi: 10.2147/DMSO.S447659. PMID: 38529169; PMCID: PMC10962461.
- Lebovitz HE. Insulin resistance: definition and consequences. Exp Clin Endocrinol Diabetes. 2001;109 Suppl 2:S135-48. doi: 10.1055/s-2001-18576. PMID: 11460565.
- Dowis, Kathryn & Banga, Simran. (2021). The Potential Health Benefits of the Ketogenic Diet: A Narrative Review. Nutrients. 13. 1654. 10.3390/nu13051654.
- Bostock ECS, Kirkby KC, Taylor BV, Hawrelak JA. Consumer Reports of "Keto Flu" Associated With the Ketogenic Diet. Front Nutr. 2020 Mar 13;7:20. doi: 10.3389/fnut.2020.00020. PMID: 32232045; PMCID: PMC7082414.
- Needham N, Campbell IH, Grossi H, Kamenska I, Rigby BP, Simpson SA, McIntosh E, Bahuguna P, Meadowcroft B, Creasy F, Mitchell-Grigorjeva M, Norrie J, Thompson G, Gibbs MC, McLellan A, Fisher C, Moses T, Burgess K, Brown R, Thrippleton MJ, Campbell H, Smith DJ. Pilot study of a ketogenic diet in bipolar disorder. BJPsych Open. 2023 Oct 10;9(6):e176. doi: 10.1192/bjo.2023.568. PMID: 37814952; PMCID: PMC10594182.
- Cui Y, Blumenthal RS, Flaws JA, Whiteman MK, Langenberg P, Bachorik PS, Bush TL. Non-high-density lipoprotein cholesterol level as a predictor of cardiovascular disease mortality. Arch Intern Med. 2001 Jun 11;161(11):1413-9. doi: 10.1001/archinte.161.11.1413. PMID: 11386890.
- Norwitz NG, Soto-Mota A, Kaplan B, Ludwig DS, Budoff M, Kontush A, Feldman D. The Lipid Energy Model: Reimagining Lipoprotein Function in the Context of Carbohydrate-Restricted Diets. Metabolites. 2022 May 20;12(5):460. doi: 10.3390/metabo12050460. PMID: 35629964; PMCID: PMC9147253.
- Soto-Mota A, Flores-Jurado Y, Norwitz NG, Feldman D, Pereira MA, Danaei G, Ludwig DS. Increased low-density lipoprotein cholesterol on a low-carbohydrate diet in adults with normal but not high body weight: A meta-analysis. Am J Clin Nutr. 2024 Mar;119(3):740-747. doi: 10.1016/j.ajcnut.2024.01.009. Epub 2024 Jan 17. PMID: 38237807.
- Mattson MP, Longo VD, Harvie M. Impact of intermittent fasting on health and disease processes. Ageing Res Rev. 2017 Oct;39:46-58. doi: 10.1016/j.arr.2016.10.005. Epub 2016 Oct 31. PMID: 27810402; PMCID: PMC5411330.
- Juliette Janson, Thomas Laedtke, Joseph E. Parisi, Peter O’Brien, Ronald C. Petersen, Peter C. Butler; Increased Risk of Type 2 Diabetes in Alzheimer Disease. Diabetes 1 February 2004; 53 (2): 474–481. https://doi.org/10.2337/diabetes.53.2.474.
- Hamzé R, Delangre E, Tolu S, Moreau M, Janel N, Bailbé D, Movassat J. Type 2 Diabetes Mellitus and Alzheimer's Disease: Shared Molecular Mechanisms and Potential Common Therapeutic Targets. Int J Mol Sci. 2022 Dec 4;23(23):15287. doi: 10.3390/ijms232315287. PMID: 36499613; PMCID: PMC9739879.