Ketogenic and low-carbohydrate diets often focus on a specific carbohydrate target: keep your net carbs under 30 grams. But as registered dietitian and certified diabetes educator Franziska Spritzler demonstrates in this presentation from Metabolic Health Summit, a carbohydrate target is not a therapy. Effective implementation means a full assessment of medical history, medications, labs, food preferences, lifestyle, and the motivation that will carry a patient through year one and beyond.

Spritzler specializes in low-carbohydrate and ketogenic nutrition and has extensive experience helping people use these approaches to improve metabolic health. she walks through the practical decisions clinicians face: when a ketogenic diet is warranted versus a more flexible low-carbohydrate approach, why she recommends 1.2 to 1.8 grams of protein per kilogram rather than the RDA's 0.8, how to manage medication adjustments for patients at risk of hypoglycemia or hypotension, and how to handle electrolytes, carbohydrate counting, sweeteners, and plant-based variations without losing the patient along the way.

Questions Answered in This Episode:

• What actually separates a ketogenic diet from a low-carbohydrate diet, and when does the difference matter? • Why is the protein RDA too low for long-term metabolic health, and what range does Spritzler recommend instead? • Who should avoid ketogenic diets entirely, and why are most contraindications manageable with closer supervision? • How should medications be monitored and adjusted when a patient begins carbohydrate restriction? • Should patients count net carbs or total carbs, and why are packaged "net carb" labels unreliable? • Can a ketogenic diet be done as a vegetarian or vegan?

A practice-tested blueprint for turning carbohydrate restriction from a prescription into a therapy patients can sustain.

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Defining ketogenic and low-carbohydrate therapy

• A ketogenic diet is high in fat, moderate in protein, and very low in carbohydrate, with the purpose of reaching nutritional ketosis beginning at about 0.5 mmol/L beta-hydroxybutyrate; for most people this means less than about 30 g net carbohydrate per day.
• Net carbohydrate here means total carbohydrate minus fiber naturally occurring in foods. A ketogenic diet can include meat, fish, eggs, cheese, non-starchy vegetables, smaller amounts of berries, nuts and seeds, and minimally processed fats and oils.
• A low-carbohydrate diet is more flexible in fat and protein and generally provides about 30-100 g net carbohydrate per day, with beta-hydroxybutyrate below 0.5 mmol/L. It can include everything in a ketogenic diet plus more starchy vegetables, medium-sugar fruits, beans, legumes, and sometimes grains, but it may not be as effective for some conditions.

Assessment before changing the diet

• A full assessment before dietary intervention includes current and past medical problems, family history, medications and supplements, diet and weight history, previous keto or low-carb experience, food preferences, allergies or sensitivities, and a three-day food record.
• The assessment also includes lifestyle factors such as eating out, travel, cooking, physical activity, family and social support, short- and long-term goals, and especially the underlying "why" that can maintain commitment when motivation falls.
• Baseline labs usually include a comprehensive metabolic panel, complete blood count, HbA1c, standard lipid panel, sometimes advanced lipoprotein markers, vitamin D, and fasting insulin for most people who are not taking insulin.

Protein and carbohydrate targets

• The protein RDA of 0.8 g/kg/day may prevent outright deficiency, but it is not enough for optimal long-term metabolic health. Plant and animal protein are not equivalent in essential-amino-acid content and bioavailability, so more plant protein is needed to reach the same protein quality.
• Protein needs become more important with aging because muscle becomes less efficient at incorporating essential amino acids, and inadequate protein during weight loss or low activity can increase lean-mass loss. Preserving muscle supports metabolic health, strength, function, and quality of life.
• A practical protein range is 1.2-1.8 g/kg of actual or ideal body weight, especially using ideal weight when BMI is over 30, with about 1.5 g/kg often in the middle of the useful range. For a 145-pound or 66-kg target weight, that is roughly 79-119 g protein per day, with about 100 g in the middle.
• The carbohydrate RDA of 130 g/day is based on the brain's glucose requirement under conditions where the brain runs exclusively on glucose. The brain can use ketones for part of its energy, and the liver can make the glucose still needed by the brain and other tissues even when dietary carbohydrate is very low.
• A low-carbohydrate diet up to about 100 g/day can improve weight, blood sugar, blood pressure, and other metabolic outcomes. For epilepsy, Parkinson's disease, certain cancers, some mental-health disorders, and some insulin-resistant conditions, a ketogenic or very-low-carbohydrate level may be more useful or necessary.
• There are no head-to-head trials of 20 g versus 60 g carbohydrate, while clinical experience, patient experience, and the larger body of variable-carbohydrate research support lower carbohydrate intake as more effective for reversing type 2 diabetes, prediabetes, and other insulin-resistant conditions.

Nutritional ketosis and keto-adaptation

• Phinney and Volek defined nutritional ketosis as beta-hydroxybutyrate beginning around 0.5 mmol/L and reaching about 3 mmol/L, sometimes higher after exercise. The useful level is individual: some people have appetite, craving, mental, or physical benefits at the low end, while others need 1-2 mmol/L or higher.
• Ketosis can begin within a few days, but keto-adaptation is slower. Full adaptation to using ketones and fatty acids as major fuel sources can take several months or longer.

Contraindications and starting the diet

• Most people can safely follow a ketogenic diet, but people with inborn errors of fatty-acid metabolism cannot, and acute intermittent porphyria in genetically susceptible adults can be triggered by very-low-carbohydrate intake because it interferes with heme synthesis.
• Many other potential contraindications can still be managed with dietary adjustment, closer clinical supervision, medication titration, and coordination with specialists.
• Anorexia nervosa was traditionally viewed as a contraindication, but a pilot study combining a ketogenic diet with ketamine under psychiatric supervision found improvements in women's relationship with body image and food; more research is needed before routine implementation. [1]
• The person and clinician work as a team because this is the person's journey. Some people want to enter ketosis rapidly, while someone coming from a very high-carbohydrate, processed-food diet may do better reducing carbohydrate gradually to limit keto-flu symptoms.
• Low-carb and ketogenic diets can be sustained for years, with long-term use allowing for bumps, life changes, and periods when the diet needs adjustment without being abandoned.

Type 2 diabetes

• Type 2 diabetes involves hyperinsulinemia, insulin resistance, elevated glucose and fatty acids, and progressive beta-cell dysfunction. Diabetes can be diagnosed with HbA1c at least 6.5%, fasting glucose at least 126 mg/dL, or random glucose at least 200 mg/dL with symptoms; prediabetes includes HbA1c 5.7-6.4% or fasting glucose 100-125 mg/dL.
• There is substantial evidence for ketogenic and low-carbohydrate diets in type 2 diabetes. Recent randomized-trial meta-analysis shows a dose-response in which lower carbohydrate intake produces greater improvements in glycemic control and weight. [2]
• Virta Health's two-year study had 74% retention at that point, more than half of participants had reversed their type 2 diabetes, and about three-quarters of the ketogenic group had lost at least 5% of body weight. [3]
• For someone seeking reversal of type 2 diabetes, a very-low-carbohydrate intake around 20-30 g/day is recommended. Anyone taking glucose-lowering or blood-pressure medication that can produce hypoglycemia or hypotension needs home monitoring and prompt medication adjustment with the prescribing clinician; routine labs are typically repeated every three to six months.
• The 2015 case was a man in his late 50s who thought he had prediabetes and hypertension, but his HbA1c was 6.7%, his fasting glucose was above 120 mg/dL, and triglycerides were elevated. He was taking an antihypertensive plus diuretic, had started low carb on his own, wanted to lose about 20 pounds, and was tired with muscle cramps.
• His carbohydrate stayed below 30 g/day, protein was aimed at the moderate-to-high end of the range, and fat was used to satiety without a fixed fat target. Because his medication retained potassium and he was also restricting salt, potassium-heavy salt products were avoided, modest sodium was used, blood pressure was monitored closely, and magnesium glycinate was added for cramps.
• By February 2016 his HbA1c had fallen to 5.7%, triglycerides were normal, muscle cramps were gone, he had lost 20 pounds, hunger was low, and he felt mentally stronger and calmer while enjoying the diet.
• His HbA1c stayed about 5.6-5.8% through December 2019, then later rose into roughly the 6.0-6.7% range after major family stress, job loss, and a less strict low-carb diet with more snacking, dark chocolate, and extra carbohydrate. He kept the 20-pound weight loss and became motivated to tighten the diet again before starting metformin.

Type 1 diabetes

• Type 1 diabetes is an autoimmune disease that destroys pancreatic beta cells, and people with type 1 diabetes still require insulin regardless of diet unless a cure becomes available. Diagnostic glucose criteria are the same as type 2 diabetes, with pancreatic autoantibodies helping identify type 1 disease.
• The research base is smaller because type 1 diabetes is much less common, but the higher-quality research supports carbohydrate reduction for better glycemic control and other improvements, including weight loss when needed.
• The TypeOneGrit survey of roughly 300 adults and children following Dr. Richard Bernstein's very-low-carbohydrate approach at about 30 g/day found an average HbA1c just under 5.7% and a glucose standard deviation around 28 mg/dL, with very narrow glucose variability in this community. [4]
• Fewer carbohydrates make insulin dosing more predictable. If a bowl of rice estimated at 45 g carbohydrate is wrong by 20%, the insulin mismatch can be large; if cauliflower rice contains about 5 g carbohydrate, the same percentage error is only about 1 g and is much less likely to change the insulin dose.
• People eating fewer carbohydrates use less mealtime insulin and may also need less basal insulin. Clinician support is important for insulin adjustment, although many people with type 1 diabetes have had to learn to adjust doses themselves because their clinicians do not support very-low-carbohydrate diets.
• Home monitoring means frequent glucose checks, especially when the diet is changing, CGM to see trends and head off highs or lows, ketone monitoring when using ketogenic therapy, and the same routine laboratory follow-up as type 2 diabetes except fasting insulin.
• The 2014 case was a man in his mid-40s who had recently started insulin and a ketogenic diet after a type 1 diabetes diagnosis. His HbA1c fell from 12.5% to 5.5%, his home glucose was mostly in the 80s to low 100s, and he needed only very small basal insulin doses during the honeymoon phase.
• The honeymoon can last up to about a year in many people, and case studies indicate that very-low-carbohydrate diets may prolong it. This client tracked food, macronutrients, insulin, and glucose in detail; his successful diet remained unchanged, glucose and ketones were monitored closely, and he carried rapid-acting glucose for hypoglycemia even on tiny basal doses.
• His LDL-C later rose from 137 to 224 mg/dL and ApoB reached 150 mg/dL, a pattern now recognized as classic lean-mass hyper-responder physiology. Because he wanted to stay ketogenic without a statin, keto-compatible fiber from avocado, berries, nuts, and seeds was increased and some butter and cream were reduced, followed by periodic lab checks.
• About seven years later he was still doing well, eating somewhat more carbohydrate because he is very active and finds it easier to sustain, using small bolus doses after a honeymoon that lasted about two years, and rotating similar meals to make insulin responses predictable. His LDL-C and ApoB remained somewhat high but acceptable to him and his doctor, and his CGM time in range was about 98%.

Polycystic ovary syndrome

• PCOS is an endocrine disorder in reproductive-age women involving genes, chronic low-grade inflammation, androgen excess, impaired reproductive-hormone balance, and in most women hyperinsulinemia and insulin resistance. Effects can include excess facial or body hair, scalp hair loss, deeper voice, acne, ovulatory dysfunction, irregular periods, infertility, and often central obesity.
• PCOS is commonly managed with metformin for insulin sensitivity, spironolactone for androgen effects, and birth-control pills for menstrual regulation. Diagnosis requires two of three findings after other disorders are excluded: clinical or biochemical hyperandrogenism, ovulatory dysfunction, or polycystic ovaries on ultrasound.
• Women with PCOS often have higher testosterone and luteinizing hormone and lower progesterone and sex-hormone-binding globulin. The keto and low-carb studies are small, but meta-analyses of randomized trials support improvements in weight and hormonal balance, including insulin.
• A study followed 12 women with PCOS and overweight or obesity after none became pregnant in an IVF cycle. They then used a ketogenic diet for about 14 weeks before another IVF cycle, after which two-thirds became pregnant and carried to term and all improved their weight and hormonal balance. [5]
• Either ketogenic or low carbohydrate can be used, and the transition can be fast or slow. Monitoring focuses on symptoms such as ovulation, hunger, energy, and mental well-being, with metabolic and reproductive labs repeated about every three to six months.
• The 2015 case was a 33-year-old woman with lean PCOS, years of irregular periods and infertility, a prior successful IVF pregnancy, and a recent failed second IVF cycle. She was taking 500 mg metformin daily, eating a very high-carbohydrate diet with frequent sweets, sometimes eating frozen yogurt for dinner, and wanted to conceive naturally without more IVF.
• The plan started slowly below 100 g carbohydrate per day, kept protein up, allowed fat to appetite, included both starchy and non-starchy vegetables, encouraged fatty fish and some red meat, kept healthy snacks available, and minimized sweets; she also changed her sweetened coffee creamer.
• Her period returned by April, she conceived naturally by June, and she carried a healthy baby to term while continuing the diet. Lower carbohydrate or ketosis may be needed by some women with PCOS, but under 100 g/day was enough for her.

Practical resources and ketone monitoring

• Individualized recommendations can be paired with simple resources for what a healthy plate looks like, the best protein, fat, and carbohydrate sources, how to use leftovers, and how to eat out.
• Food tracking is especially useful at the beginning because people often underestimate or overestimate carbohydrate, protein, and fat. Cronometer can also track micronutrients, while KetoDiet and Carb Manager are other low-carb-focused options; long-term tracking is optional unless the person finds it useful.
• Ketone monitoring can confirm ketosis and help identify the beta-hydroxybutyrate level at which a person feels best. Blood beta-hydroxybutyrate is the gold-standard method; breath meters and urine strips are other options but have weaker evidence behind them.

Electrolytes and keto-flu symptoms

• When insulin falls on a ketogenic diet, people lose fluid and electrolytes, which can contribute to dizziness, fatigue, muscle cramps, and the general keto-flu feeling. Hydration and mineral intake continue to matter after the initial transition.
• Roughly 3-7 g sodium per day from food plus added sodium or salty foods is used when appropriate. Congestive heart failure, uncontrolled hypertension, and chronic kidney disease require individualized sodium guidance from the medical provider.
• Potassium is widely available in keto-friendly animal and plant foods such as meat, fatty fish, greens, avocado, nuts, and seeds, so many people can meet their needs from food.
• Magnesium is harder to obtain in large amounts from food; the target is roughly 320-400 mg/day, with supplementation such as magnesium glycinate or Slow-Mag when needed.

Net carbohydrate and packaged keto foods

• The classic ketogenic definition of net carbohydrate is total carbohydrate minus fiber naturally occurring in food, because that fiber is not digested and absorbed into the bloodstream in the same way as digestible carbohydrate.
• Packaged keto products often subtract added processed fibers and sugar alcohols from total carbohydrate, but some of these ingredients can be partly digested, absorbed, and raise blood glucose. An avocado's natural fiber subtraction is not equivalent to assuming every added fiber or sugar alcohol in a packaged bar has no glycemic effect.
• Whole foods are the main focus, with naturally occurring fiber subtracted. For processed foods with added fiber and sugar alcohols, at least half of those carbohydrates are generally counted, with erythritol as an exception.
• Newer fiber formulations may behave differently, and some people do not see a glucose rise, but anyone who needs a very strict ketogenic therapy should test their own glucose because individual responses can differ.

Sweeteners

• Sweetener use depends on the person and the sweetener. The listed sweeteners generally have minimal effects on blood glucose, insulin, and by extension ketones in studies, but results vary across studies and individuals.
• Allulose is a preferred sweetener because many randomized trials have found increased incretin hormones and lower glucose, including in type 2 diabetes, but a randomized controlled trial in people with type 2 diabetes did not find those glucose or incretin benefits. [6]
• Research on sweeteners and the gut microbiome is mixed: some studies find adverse microbiome or glucose-regulation effects and other randomized trials do not find that relationship.
• Some people do best avoiding some or all sweeteners because they trigger cravings, hunger, or other side effects. Others can use small amounts regularly without problems, and that flexibility may help sustain nutritional ketosis.

Vegetarian and vegan ketogenic diets

• A vegetarian or vegan ketogenic diet is possible, but it is harder than an omnivorous ketogenic diet because adequate protein has to be reached while carbohydrate remains low. Lacto-ovo vegetarian keto is easier because eggs and cheese provide protein without much carbohydrate, whereas whole plant protein sources also bring digestible carbohydrate.
• A vegan ketogenic diet may require more coconut oil or MCT oil to maintain ketosis, and micronutrient supplementation is essential on a fully plant-based diet. With careful planning, both vegetarian and vegan ketogenic meal patterns can be constructed.

Empowerment and long-term self-efficacy

• The final goal is not only teaching someone how to follow the diet but helping them feel capable of doing it after the clinical work ends. People need different levels of reassurance, accountability, contact, and independence, so support should match the person.
• The client or patient has to remain an active participant because they will make the long-term decisions about food and how to handle real-life situations. Guidance remains available without making the person dependent on the clinician.
• Motivation is usually high at the beginning when hunger falls, glucose improves, and weight is coming down, but enthusiasm can fade. Returning to the original "why" reconnects the diet to the health outcome that mattered enough to begin.
• Perfect glucose or a perfectly predictable rate of weight loss are unrealistic expectations. The useful focus is on controllable actions: food and beverage choices, movement, stress management, mindset, and attitude.
• Everyone slips sometimes. Failures become learning opportunities by reviewing what happened as a team and building a strategy for the next time a similar situation occurs.

References

1. [18:23] Ketogenic diet and ketamine infusion treatment to target chronic persistent eating disorder psychopathology in anorexia nervosa: a pilot study — https://doi.org/10.1007/s40519-022-01455-x
2. [21:05] Dose-dependent effect of carbohydrate restriction for type 2 diabetes management: a systematic review and dose-response meta-analysis of randomized controlled trials — https://doi.org/10.1093/ajcn/nqac066
3. [21:16] Long-Term Effects of a Novel Continuous Remote Care Intervention Including Nutritional Ketosis for the Management of Type 2 Diabetes: A 2-Year Non-randomized Clinical Trial — https://doi.org/10.3389/fendo.2019.00348
4. [27:50] Management of Type 1 Diabetes With a Very Low-Carbohydrate Diet — https://doi.org/10.1542/peds.2017-3349
5. [38:45] Adding a ketogenic dietary intervention to IVF treatment in patients with polycystic ovary syndrome improves implantation and pregnancy — https://doi.org/10.1016/j.reprotox.2023.108420
6. [49:04] Short-term effects of allulose consumption on glucose homeostasis, metabolic parameters, incretin levels, and inflammatory markers in patients with type 2 diabetes: a double-blind, randomized, controlled crossover clinical trial — https://doi.org/10.1007/s00394-023-03205-w :::