If you're having trouble concentrating on a ketogenic diet it's likely that you're not eating enough vegetables, and might be eating too much protein.
Too much protein can take you out of ketosis, but people think they can just eat lean hamburger three times a day.
If the fat/protein ratio is right, the inability to focus can be a symptom of electrolyte deficiency, particularly sodium, potassium, and magnesium. You should be getting potassium and magnesium from vegetables, but supplements can be a useful diagnostic tool: If you take 400 mg of potassium and find, an hour later, that you're thinking more clearly, that's data.
Don't overdo it with electrolyte supplements, though; too much sodium can increase the calcium in your blood enough to give you kidney stones, if you're lucky, and worse effects if you're unlucky. Too much potassium can mess with your heart.
Eating more protein doesn't take you out of ketosis, that's just a myth; it will just lower the amount of keytones that are being produced. If only are protein or nothing at all and you would still be in ketosis.
Too much protein can take you out of ketosis, but people think they can just eat lean hamburger three times a day.
If the fat/protein ratio is right, the inability to focus can be a symptom of electrolyte deficiency, particularly sodium, potassium, and magnesium. You should be getting potassium and magnesium from vegetables, but supplements can be a useful diagnostic tool: If you take 400 mg of potassium and find, an hour later, that you're thinking more clearly, that's data.
Don't overdo it with electrolyte supplements, though; too much sodium can increase the calcium in your blood enough to give you kidney stones, if you're lucky, and worse effects if you're unlucky. Too much potassium can mess with your heart.