Quick answer: Common keto mistakes include not eating enough fat, eating too many hidden carbs, not drinking enough water or replacing electrolytes, skimping on vegetables and not planning meals. Early on, the body loses water and sodium as glycogen is used up, which can cause fatigue and headaches. Planning ahead, hydrating and eating plenty of non-starchy vegetables help.
Key takeaways
Eating too little fat on keto can leave you hungry and tired, since fat replaces carbohydrates as the main fuel.
Hidden carbohydrates in sauces, snacks and drinks add up quickly.
Drinking enough water, eating plenty of non-starchy vegetables and planning meals ahead help avoid the most common slips.
Not eating enough fat
On keto, fat replaces carbs as the main fuel. Too little can leave you hungry and tired. See fat intake.
Eating too many carbs
Hidden carbs in sauces, snacks and drinks add up. See net carbs.
Not drinking enough water
Water weight loss
Glycogen is stored with water, so using it up releases water, especially early.
Electrolyte balance
Lower insulin makes the kidneys excrete more sodium, and potassium and magnesium can drop too. See balancing electrolytes.
Appetite
Thirst is sometimes mistaken for hunger.
Not eating enough vegetables
Non-starchy vegetables provide fiber, vitamins, minerals and antioxidants with few carbs.
Not planning ahead
Without a plan, it’s easy to slip on carbs or make impulsive choices. Plan meals, shop with a list and batch cook, and keep keto snacks on hand.
Healthy aging lens
Sustainability matters most. A plan you can keep, built on whole foods, supports long-term health better than a strict diet you abandon.
What the research shows
Common keto mistakes, such as too little protein, poor fat quality or unrealistic expectations, show up in research results.
Keto under tightly controlled conditions (Hall 2016, metabolic ward study). 17 men with overweight or obesity lived on a research ward, eating a high-carbohydrate diet for 4 weeks and then a ketogenic diet with the same calories and protein for 4 weeks. Energy use rose a little on keto (about 57 to 151 kcal a day depending on the method), but body fat loss actually slowed, while loss of lean mass increased. A limitation is that there were only 17 men, the diets were not randomized in order, and 4 weeks may be too short to see longer-term adaptation.
Six weeks of keto in healthy adults (Urbain 2017, before-and-after study). 42 healthy adults followed a ketogenic diet (about 72% fat, 21% protein and 8% carbohydrate) without calorie limits for 6 weeks. They lost about 2 kg, split equally between fat and lean mass. Peak power dropped 4%, LDL cholesterol rose about 11%, and insulin fell 22%. A limitation is that there was no control group, so changes can’t be fully separated from other factors.
Keto vs. low-fat over a year or more (Bueno 2013, meta-analysis of 13 randomized trials). This review pooled trials lasting at least 12 months that compared a very-low-carbohydrate ketogenic diet (50 g of carbohydrate a day or less) with a low-fat diet in 1,415 adults. The keto groups lost about 0.9 kg more, had lower triglycerides and slightly lower diastolic blood pressure, and had higher HDL cholesterol. They also had higher LDL cholesterol (about 0.12 mmol/L). A limitation is that the average extra weight loss was small, and people in these trials often drifted away from strict keto over time.
Strength of the evidence: These studies suggest keto works best with adequate protein, attention to cholesterol and realistic expectations.
When to see a naturopathic doctor
It may be time to see a naturopathic doctor if you have diabetes or take insulin, sulfonylureas or SGLT2 inhibitors (risk of low blood sugar or ketoacidosis), or if you take blood pressure medication or diuretics. The same is true if you have kidney, liver, gallbladder or pancreas disease, or high cholesterol, if you are pregnant, breastfeeding, or have a history of disordered eating, or if you want a keto plan tailored to your labs and goals.
See a medical provider promptly for nausea and vomiting, abdominal pain, confusion, fruity-smelling breath with rapid breathing, or very high blood sugar or ketone readings, which can signal ketoacidosis.
Want a keto plan that’s safe for your health?
A free 15-minute consultation with Dr. Kneessi. No cost, no obligation. In-office in Odenton, MD or by telehealth.
Questions to bring to your clinician
These questions can help you get the most out of your next visit.
Which of these common mistakes am I most likely to make with my routine?
Which keto mistake am I most likely to make, given my habits?
How can I avoid hidden carbs in the foods I usually eat?
What should I do if I stall or feel unwell on keto?
Frequently asked questions
Why am I tired on keto?
Often from dehydration and low electrolytes early on.
Can I eat too many carbs on keto?
Yes, hidden carbs can keep you out of ketosis.
Do I need more water on keto?
Many people do, especially early.
Should I eat vegetables on keto?
Yes, non-starchy vegetables are essential.
Sources
- Kreitzman SN, Coxon AY, Szaz KF. Glycogen storage: illusions of easy weight loss, excessive weight regain, and distortions in estimates of body composition. Am J Clin Nutr 1992. PMID: 1615908. https://pubmed.ncbi.nlm.nih.gov/1615908/
- Brands MW, Manhiani MM. Sodium-retaining effect of insulin in diabetes. Am J Physiol Regul Integr Comp Physiol 2012. PMID: 23034715. https://pmc.ncbi.nlm.nih.gov/articles/PMC3533616/
- Slavin JL, Lloyd B. Health benefits of fruits and vegetables. Adv Nutr 2012. PMID: 22797986. https://pmc.ncbi.nlm.nih.gov/articles/PMC3649719/
- Dansinger ML, et al. Comparison of the Atkins, Ornish, Weight Watchers, and Zone diets for weight loss and heart disease risk reduction: a randomized trial. JAMA 2005. PMID: 15632335. https://pubmed.ncbi.nlm.nih.gov/15632335/
- MedlinePlus: Fluid and Electrolyte Balance
- MedlinePlus: Sodium
- Hall KD, et al. Energy expenditure and body composition changes after an isocaloric ketogenic diet in overweight and obese men. Am J Clin Nutr 2016. PMID: 27385608. https://pubmed.ncbi.nlm.nih.gov/27385608/
- Urbain P, et al. Impact of a 6-week non-energy-restricted ketogenic diet on physical fitness, body composition and biochemical parameters in healthy adults. Nutr Metab (Lond) 2017. PMID: 28239404. https://pubmed.ncbi.nlm.nih.gov/28239404/
- Bueno NB, et al. Very-low-carbohydrate ketogenic diet v. low-fat diet for long-term weight loss: a meta-analysis of randomised controlled trials. Br J Nutr 2013. PMID: 23651522. https://pubmed.ncbi.nlm.nih.gov/23651522/
This article is for educational purposes only and is not medical advice. It does not replace an individual evaluation. Talk with your healthcare provider before starting supplements or changing medications, especially if you are pregnant, nursing, or managing a health condition.
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