Net carbs is simply total carbs minus fiber and non-digestible sugar alcohols, like erythritol. (This doesn’t apply to high glycemic sugar alcohols, like maltitol.) We don’t have to count fiber and certain sugar alcohols in net carbs, because they either don’t get broken down by our bodies, are not absorbed, or are absorbed but not metabolized. (Read more about sugar alcohols here.)
In the mid-1990s, Hollywood producer Jim Abrahams, whose son's severe epilepsy was effectively controlled by the diet, created the Charlie Foundation to promote it. Publicity included an appearance on NBC's Dateline programme and ...First Do No Harm (1997), a made-for-television film starring Meryl Streep. The foundation sponsored a multicentre research study, the results of which—announced in 1996—marked the beginning of renewed scientific interest in the diet.
There are theoretically no restrictions on where the ketogenic diet might be used, and it can cost less than modern anticonvulsants. However, fasting and dietary changes are affected by religious and cultural issues. A culture where food is often prepared by grandparents or hired help means more people must be educated about the diet. When families dine together, sharing the same meal, it can be difficult to separate the child's meal. In many countries, food labelling is not mandatory so calculating the proportions of fat, protein and carbohydrate is difficult. In some countries, it may be hard to find sugar-free forms of medicines and supplements, to purchase an accurate electronic scale, or to afford MCT oils.
"I recommend only 5 percent of calories coming from carbs, which usually averages out to less than 30 grams," he says. "I understand why people get nervous and panic, thinking 'Can I even eat a salad?' This is why I recommend tracking only 'net carbs', which are total carbs minus fiber. For example, an avocado has 12 grams of carbs but 10 grams of fiber, which means it has 2 grams of net carbs. Also, green leafy vegetables are very nutritious and contain a lot of fiber, so you can almost eat them as much as you want and stay below your limit.
Most people will choose to begin their carb-up on Friday night and end it before bed on Saturday. This is usually most convenient as it's when you are off of work and can relax and enjoy the process. If you aren't overly concerned with fat loss and are just using this diet as a way to maintain blood sugar levels, you can likely eat whatever carbohydrate foods you like during this period. If you are worried about fat gain though, then you need the math.
For patients who benefit, half achieve a seizure reduction within five days (if the diet starts with an initial fast of one to two days), three-quarters achieve a reduction within two weeks, and 90% achieve a reduction within 23 days. If the diet does not begin with a fast, the time for half of the patients to achieve an improvement is longer (two weeks), but the long-term seizure reduction rates are unaffected. Parents are encouraged to persist with the diet for at least three months before any final consideration is made regarding efficacy.
Variations on the Johns Hopkins protocol are common. The initiation can be performed using outpatient clinics rather than requiring a stay in hospital. Often, no initial fast is used (fasting increases the risk of acidosis, hypoglycaemia, and weight loss). Rather than increasing meal sizes over the three-day initiation, some institutions maintain meal size, but alter the ketogenic ratio from 2:1 to 4:1.