Originally Posted by eandc2006
Please elaborate more on the shock and the readjustment? Maintainence in ip is very low Arab still and I really don't want to upset my metabolism or damage my thyroid. How does one readjust after the initial shock? What is hypo? Maybe that is why I am losIng so slow because I have messed up my diet with so many diets. Is ip harmful in the long run? Can it cause health problems? I am confused
Sorry, I have been a bit busy recently. I am currently digging into studies on this topic. I am not familiar with endocrinology and it takes a while to figure out what is known and what is just assumed knowledge. Most studies looking at hormones and nutrition have been done in animals, not people. So, it is hard to extrapolate the findings.
After going low calorie and low carb, your body reacts as if being in starvation. Your metabolism is adjusting to what is perceived as a threat to survival. Ketosis is one adaptive mechanism and if you stay in ketosis for a longer period, your body will react by switching to using fat as the main energy source. Fat versus carb usage affects many organs and tissues in your body. So, it makes sense that hormones not only control what type of energy is used, but their levels are also controlled by the energy source available. Ideally, everything is in balance and adapted to the current situation. When you change that situation, changes are enforced and reaching a new balance usually takes a couple of weeks. There is nothing you need to do. Just wait and don't add additional stressors like exercise etc.
Your body usually runs on carbohydrates as the main source of energy. How carbs are used is controlled mainly through three hormones: Insulin, leptin, and grehlin (there are others, but their action is not yet known well). These hormones control the usage of carbohydrates (glucose) by the different cells in your body and they control whether your body thinks it needs more of the same energy source (=hunger) or not (=satiated). Besides your immediate energy needs, your body also has different needs for energy during your sleep/awake cycles and during the different phases of reproduction etc. These functions are all coordinated with each other. It appears thyroid hormones act as a kind of master switch to do this. When your body goes into starvation mode, the levels of active T3 thyroid hormones also go down and this may be the reason why your overall metabolism slows. This is just a short-term reaction. It appears to happen in the liver and it is probably controlled independently of the thyroid gland. You still get thyroid hormones secreted from the gland, hence TSH ad T4 levels appear normal. If you are not hypo(thyroid), you probably just feel a bit sluggish until your body readjusts T3 production in the liver.
For people who are deficient in thyroid production in the gland, however, the situation may become problematic. I think there is the possibility that the overall lack of thyroid hormone activity re-enforces the lack of insulin/leptin signal in some people to an extent that their bodies never properly adjust to ketosis (or the low calories). In this case, you have to eat above 100g of carbs/day for a longer period of time to get your systems properly going again. I also had the impression, that my immune system became hyperactivated. If you have Hashimoto's, this may worsen the situation. Particularly, as soy/broccoli may affect thyroid health on their own.
So, long story short, if you are concerned about possible effects of IP (or any other diet) it seems advisable to get your health baseline well established (complete thyroid panel, estrogen/progesterone levels if possible, and overall routine levels of vitamins, minerals, lipids, etc) before you start IP. In case of irregularities, you can then go back and compare. As to thyroid or overall health, the symptoms are quite telling (also see previous poster). If you experience them for an extended period, it is better to check. It appears most negative effects of a very low carb diet can be reversed. But there are/were people on this board where reversal did not completely occur. Just stay a bit vigilant and, if possible, work with a physician if you do IP for longer than just a couple of weeks. Lisa pointed out that the original diet on which IP is based was meant to be followed for about 10 weeks. Also, the original diet was devised for healthy (and mostly male) athletes. A perimenopausal/overweight female body is a different landscape. Despite of what IP says to promote the diet (scientific basis etc.), I am quite sure they never properly looked into hormones.