The ketogenic diet is one of the most popular weight-loss strategies today because those who stay on the diet are able to lose weight and keep it off. It works by limiting carbohydrates. The traditional ketogenic diet consists of approximately 75% of calories as fat, 20% as protein, and only 5% carbohydrates. This results in a daily carbohydrate intake of around 50 grams. With the amount of carbs being limited, the body becomes more efficient at breaking down fat into ketones for energy.
The body uses two main sources of fuel; glucose and ketones. Glucose is obtained when the body breaks down carbohydrates including sugars. The energy obtained from glucose makes one feel energetic initially but often leads to “crashing” soon after, causing hunger and weakness. If more carbohydrates are ingested than can be used by the body, the excess is stored as glycogen in the muscles and liver. When glycogen stores are full, the excess glucose is stored as fat.
If there isn’t enough glycogen or glucose available to provide energy, ketones are utilized. This energy source is steadier and doesn’t lead to cravings or the crash that often occurs with glucose. The traditional ketogenic diet is not without adverse effects. Two of these side effects are discussed below.
The Keto Flu
The keto flu can happen during the first couple weeks of starting the diet. This is your body’s response to changing from glucose to ketones for energy. The keto flu symptoms are:
- Stomach cramps
- Muscle cramps or aches
- Sore throat
- Poor sleep
- Trouble concentrating
These symptoms typically start twenty-four to forty-eight hours after beginning the diet. The more your diet was previously high in refined sugars and carbohydrates, the more severe these symptoms will likely be.
Another common side effect of the keto diet is keto breath. This “bad breath” symptom will be experience by most people who put their body into ketosis. It can occur during the first week and is the result of acetone being released from the body. This side effect is often accompanied by a metallic taste in the mouth and should go away when the body becomes accustomed to being in ketosis. Until this happens, there are some steps that can be taken to help with this pesky problem.
- Carry Breath Mints: You may not be able to get rid of the acetone on your breath, but you can mask it with breath mints. Sugar-free mints are preferred.
- Drink More Water: Drinking more water causes more ketones to be released from the body in the urine resulting in less elimination by breathing. Drinking water has other health benefits as well that I have discussed in previous posts.
- Brush Teeth Frequently: This is another simple strategy to help keep your breath fresh.
The Cyclical Ketogenic Diet (CKD)
The cyclical ketogenic diet is a variation of the ketogenic diet where you follow the 50 gm/day carb diet for 5-6 days per week followed by a higher carb diet for 1-2 days. This variation is a popular tactic for those trying to build muscle and improve exercise performance as the higher carb days or “refeeding days” replete glucose reserves. This is important as glycogen is what the body uses for energy during workouts. These “carbohydrate days” will give your body the glucose it needs during workouts while reaping the benefits of ketosis.
This type of diet has many benefits. If you don’t ever get to eat carbohydrates, you may feel deprived of some of your favorite tasting food. The CKD allows you to enjoy these foods one or two days per week. The body needs carbohydrates to function properly and carb loading keeps the body functioning smoothly.
The microbiome of the gut will be healthier if you eat more carbs. This leads to a better functioning gut-brain axis which provides several benefits.
The keto flu and keto breath are usually less severe with CKD.
It is important to be selective in the carbohydrates you consume during the CKG. Try to eat fruit, lentils, sweet potatoes, rice and oatmeal, limiting fat intake during your carbohydrate days. This is important as the body is only able to utilize one energy source at a time. Since glucose is the preferred energy source, excess fat consumed during these days will be stored as body fat. The goal should be to burn all of the glycogen consumed during the refeeding days so ketones are used as energy the rest of the week.
One Benefit of CKD - A Higher Level of Anabolic Hormones
Testosterone is one of the most important hormones for muscle growth. A high fat diet increases the concentration of testosterone in the blood. It has been shown that diets with less than 20% fats can inhibit testosterone production. This is especially true when compared to diets containing 40% fat. 1
A study by Wang et al. showed a low-fat diet decreased testosterone levels by 12%. 2
A low fat diet decreases the level of testosterone in the bloodstream which, in turn, may lead to a decrease in muscle-building capability.
Growth hormone (GH) also known as somatotropin or human growth hormone (HGH), stimulates growth and the reproduction and regeneration of cells. Low levels of this hormone may increase risk of disease and increase body fat. 3
Carbohydrates and sugar increase insulin levels. More insulin leads to less HGH so reducing carbohydrates in the diet may help to increase human growth hormone. 4
Insulin-like growth factor 1 (IGF-1)
The deficiency of Insulin-like growth factor 1 (IGF-1) is associated with metabolic syndrome. Metabolic syndrome leads to insulin resistance, increased glucose levels, impaired lipid profile, cardiovascular disease and obesity. All of these effects are undesirable. The ketogenic diet increases IGF-1 which may lessen the chances of contracting metabolic syndrome and the negative effects described above. 6
A Great Supplement For Keto Dieters
If there isn’t enough glycogen or glucose available to provide energy, ketones are utilized. This happens even when we consume a regular diet during the night as we sleep. As mentioned above, this energy source is steadier and doesn’t lead to cravings or the crash that often occurs with glucose. There are three ketone bodies. These are acetoacetate, BHB, and acetone. Beta-hydroxybutyrate is a great energy source when eating a ketogenic diet. When glucose is limited, mental concentration can be negatively affected. 7
BHB salt supplements can be used when energy levels are low while on the ketogenic diet.
The ketogenic diet has become very popular. This diet works by forcing the body to break down fat for energy. For those who work out, the cyclical ketogenic diet is likely a better option. This diet allows for one to two days per week of carbohydrate loading to build up glycogen stores for quick energy supply during physical exertion. It is important to eat “clean” carbohydrates rather than junk food. Remember when carb loading to avoid too many fat calories because the body can only utilize one energy source at a time. Finally, consider utilizing BHB salts for energy during the beginning of your keto diet and anytime you feel sluggish. This supplement can get you over the hump without resorting to eating too many carbohydrates. If you have any questions regarding the ketogenic or cyclical ketogenic diet, please feel free to contact me. If I don’t know the answer to your question, I will research it and get back to you as soon as possible. Thank you for reading my post.
Michael J. Brown, RPh, BCPS, BCPP
Mr. Brown is a Clinical Pharmacist specializing in pharmacotherapy and psychiatry.
Feel free to send Michael a message using this link.
- Hämäläinen E, Adlercreutz H, Puska P, Pietinen P. Diet and serum sex hormones in healthy men. J Steroid Biochem. 1984 Jan;20(1):459-64. PubMed PMID: 6538617.
- Wang, C et al. Low-fat high-fiber diet decreased serum and urine androgens in men. J Clin Endocrinol Metab. 2005; 90(5): 3550-9.
- Carroll PV, Christ ER, Bengtsson BA, Carlsson L, Christiansen JS, Clemmons D, Hintz R, Ho K, Laron Z, Sizonenko P, Sönksen PH, Tanaka T, Thorne M. Growthhormone deficiency in adulthood and the effects of growth hormone replacement: a review. Growth Hormone Research Society Scientific Committee. J Clin Endocrinol Metab. 1998 Feb;83(2):382-95. Review. PubMed PMID: 9467546.
- Lanzi R, Luzi L, Caumo A, Andreotti AC, Manzoni MF, Malighetti ME, Sereni LP, Pontiroli AE. Elevated insulin levels contribute to the reduced growth hormone(GH) response to GH-releasing hormone in obese subjects. Metabolism. 1999 Sep;48(9):1152-6. PubMed PMID:10484056.
- Greenwood FC, Landon J, Stamp TC. The plasma sugar, free fatty acid, cortisol, and growth hormone response to insulin. I. In control subjects. J Clin Invest. 1966;45(4):429–436. doi:10.1172/JCI105357.
- guirre, G.A., De Ita, J.R., de la Garza, R.G. et al. Insulin-like growth factor-1 deficiency and metabolic syndrome. J Transl Med 14, 3 (2016) doi:10.1186/s12967-015-0762-z.
- White H, Venkatesh B. Clinical review: ketones and brain injury. Crit Care.2011Apr6;15(2):219.doi:10.1186/cc10020. Review. PubMed PMID: 21489321; PubMed Central PMCID: PMC3219306.