Several things make me very leery of going low-carb, or at least make me feel that it is counterproductive:
1) Several authors, such as Diana Schwarzbein and Barry Sears talk about cortisol being raised on a low-carb diet as if it were common biochemistry knowledge. Knowing what I know about cortisol, a low-carb diet seems very undesirable. Diana Schwarzbein repeats the mantra that “going too low in carbohydrates raises cortisol and adrenaline” time and time again throughout her work. Keep in mind she observed this by tracking her patients’ hormone levels as a practicing endocrinologist. Barry Sears emphatically states:
“…the longer you stay in ketosis, the more your fat cells adapt so that they are transformed into ‘fat magnets,’ becoming 10 times more active in accumulating fat…A high-protein, low-carbohydrate diet drives insulin levels too low, thereby causing hypotension, fatigue, irritability, lack of mental clarity, loss of muscle mass, increased hunger, and rapid fat regain when carbohydrates are reintroduced into the diet. Not exactly a prescription for anti-aging. This coupled with the increase in cardiovascular mortality because insulin levels are too low, simply reinforces the need to maintain insulin within a zone: not too high, not too low.”
This is probably due to cortisol, particularly the “fat magnet” claim. Although not everyone experiences these things on a low-carb diet, I experienced almost all of them, and know many others who have as well. The longer I went low-carb, the worse those symptoms got.
2) My own personal health eventually deteriorated on a low-carb diet. My pet allergies and asthma increased, I had digestive problems – both heartburn and mild constipation, became very grouchy, and developed foul body and breath odor, and even eventually started to have tooth pain (although on zero carb I did not). Add sleep problems and the re-appearance of gas and slight acne to the list too. I had none of these experiences in the beginning stages. Quite the contrary actually. Everything seemed to improve and I had thought, like many do, that I had found the Holy Grail of health. Note: I was the perfect low-carber too. All my dairy products and meats were grassfed/pastured and local. My dairy was unpasteurized. All my produce was organic – most from farmer’s markets.
“…remember that prolonged dieting [including ‘this one’] tends to shut down thyroid function. This is usually not a problem with the thyroid gland but with the liver, which fails to convert T4 into the more active thyroid principle, T3. The diagnosis is made on clinical grounds with the presence of fatigue, sluggishness, dry skin, coarse or falling hair, an elevation in cholesterol, or a low body temperature.”
5) The most major metabolic and digestive problems that people have come to me seeking help for were caused by going too low in carbohdyrates for a long period of time. One kid had ruined his digestion and metabolism so severely that he developed hypogonadism, was suicidal, and couldn’t manage to choke down more than 1,500 calories per day without severe bloating. This was a formerly-healthy young man in his 20’s that did this to himself by being totally dedicated to good health. His diet consisted of mostly raw dairy products, raw grassfed beef, and sauerkraut – a combination of following ideas derived from Wolfgang Lutz, Aajonus Vonderplanitz, and the Weston A. Price Foundation. Only a fruitarian diet seems to be capable of matching this level of degeneration.
6) Broda Barnes stated:
“…it has been clearly established that a high protein diet lowers the metabolic rate, [therefore] symptoms of hypothyroidism will be aggravated… Hypoglycemia may be controlled on the high protein diet, but the other symptoms of thyroid deficiency which usually accompany hypoglycemia are aggravated.”
“…when the diet was changed so that it was low in fat but high in protein and with enough carbohydrate to prevent diarrhea, symptoms of hypothyroidism appeared. Cholesterol level in the blood became elevated and in order to keep it within normal range, four additional grains of thyroid daily were needed. Apparently, a diet high in protein requires additional thyroid for its metabolism.”
7) Given the ongoing topic of omega 6 overload on the cellular level, a high fat/low-carb diet is almost always higher in total omega 6 polyunsaturated fat as well – even if vegetable oils are excluded. This may be very significant, it may not be the end of the world. The issue needs further exploration. A low-carb diet will typically have twice the amount of omega 6 as a typical, low vegetable-oil diet with more calories coming from carbohydrate. My estimates, using ESHA software, of my low-carb diet included at least 15 grams of omega 6 per day. My diet over the past several days has had an average of just 3 grams of omega 6 per day. Significant? Who knows, but it’s thought-provoking.
This is just a short list of reasons. But you get the idea. It’s not that a low-carb or even zero-carb diet can’t be a healthy diet. Eskimos proved that beyond a shadow of a doubt. The question is, given that the world seems to be in metabolic decline, with widespread insulin resistance, low body temperature, and more… is a low-carb diet the most effective strategy at fixing the core problem, or might it actually be counterproductive?