After more than 30 days of increasing my carb intake it looks like my cholesterol numbers have all improved. At this point I haven’t bothered to check my blood ketones because I know that I’m out of ketosis. I’ve been trying to keep my carb intake to around 100 gm per day. Sometimes I go over and sometimes I go under, but on average it’s around 100 gm.
When I last left off in Part 3, I was still trying to piece together the possible causes for my sky high cholesterols despite being in ketosis. The possible explanations left were:
Increased consumption of saturated fats -> Increased liver production of fats -> High serums cholesterol
- Deficiency in certain micronutrients such as choline and copper -> Through some unknown mechanism -> High serum cholesterol
- Natural response of the body being in ketosis is to mobilize more fat for energy -> Higher serum cholesterol
- Chronic low carb -> Hypothyroidism (low T3) -> Decreased expression of LDL receptors in the liver -> Higher serum cholesterol
The next step in my experiment will be to add in a copper supplement taking the 2mg/day recommend by The Perfect Health Diet folks. I’ll continue my consumption of eggs since yolks are a good source of choline and I’ll start eating coconut oil and grassfed butter again.
I was in the midst of taking the copper supplements when I finally started putting 2 and 2 together regarding my ketosis rash, prurigo pigmentosa. In an effort to explore my suspicions about the rash, I started to eat more carbs, which confirmed my diagnosis after the rash promptly went away (my skin is still rash free).
Unfortunately, during all this, the copper supplementation fell by the wayside, so I don’t really have anything to report on it.
What I think is most interesting however were the results from my follow up thyroid panel, obtained at the same time as this test. After adding more carbs back into my diet we see that my thyroid numbers (previously in the hypothyroid or near hypothyroid range) have normalized, while simultaneously my LDL and total Cholesterol have also improved.
This really lends credence to hypothesis 4:
Chronic low carb -> Hypothyroidism (low T3) -> Decreased expression of LDL receptors in the liver -> Higher serum cholesterol
As I was trying to piece all of this together, Chris Kresser put out a timely article discussing LDL particles and the different factors that affect them, with one explanation for elevated LDLs really catching my attention:
Poor thyroid function is another potential cause of elevated particle number. Thyroid hormone has multiple effects on the regulation of lipid production, absorption, and metabolism. It stimulates the expression of HMG-CoA reductase, which is an enzyme in the liver involved in the production of cholesterol. (As a side note, one way that statins work is by inhibiting the HMG-CoA reductase enzyme.) Thyroid hormone also increases the expression of LDL receptors on the surface of cells in the liver and in other tissues. In hypothyroidism, the number of receptors for LDL on cells will be decreased. This leads to reduced clearance of LDL from the blood and thus higher LDL levels. Hypothyroidism may also lead to higher cholesterol by acting on Niemann-Pick C1-like 1 protein, which plays a critical role in the intestinal absorption of cholesterol.
Studies show that LDL particle number is higher even in subclinical hypothyroidism (high TSH with normal T4 and T3), and that LDL particle number will decrease after treatment with thyroid hormone.
My little cholesterol n=1 experiment pretty much illustrated this exact point… it probably would have saved me a lot of trouble if he had only written this a few months earlier!! But then again, something tells me I would have wanted to test it anyways.
Since it’s well established that eating a very low carb diet can actually cause your body to shut down thyroid production in an attempt to reign in your metabolism as it shifts into ‘conserve energy mode,’ I feel pretty confident that I’ve gotten to the bottom of my elevated cholesterols. I’ll probably check it again in a few weeks to see if my numbers have normalized even more.