There has been much debate over the APOE4 genes recently. If a high carb, low fat diet was bad for us, we must understand the reasons why a high fat diet can be helpful, in the right cases.
This it seems is based on your genetic makeup. Specifically, a gene called APOE. There are 3 different types of the APOE gene which I will discuss later.
As a human being, we are given 2 of these types of APOE genes at the same time, meaning that we actively carry 2 types of genes that are instructions for our bodies on how to make apolipoprotein E, which combines with fats to form lipoproteins.
APOE Gene Types
The three different types of APOE genes are as follows:
- APOE2 – Best suited to a High Fat / Low Carb Diet (saturated fats are good)
- APOE3 – Suitable For Both
- APOE4 – Best Suited For A High Monounsaturated Fat / Low Carb Diet (Avoid Saturated Fats)
Don’t freak out! Saturated fats will not kill you. If you feel good on a ketogenic diet, than there should be no reason to get your genetics tested. You should be getting your cholesterol checked as part of your regular medical checkup.
Because humans have two copies of each gene, these three isoforms code for six genotypes (E2/E2, E2/E3, E2/E4, E3/E3, E3/E4, and E4/E4). Your APOE genotype determines how your body metabolises cholesterol.
If you are consuming a high fat, low carb diet, you will increase your body’s production of cholesterol.
So how does the metabolism of cholesterol influence your body’s ability to handle cholesterol?
I spoke a little about lipoproteins before. These are made up of two components, cholesterol and fat.
When you increase your dietary fat, you increase your lipoprotein levels, which triggers the body’s cholesterol production to increase. This means that a high-fat diet is equivalent to a high cholesterol diet.
APOE 2 Carriers Thrive On High Fat
This means that APOE 2 carriers thrive on a high fat diet, as Cholesterol is an important part of the body’s ability to create hormones and function correctly.
However, research studies have shown that APOE4 carriers are most effected by high cholesterol, and benefit more from a low saturated fat diet, instead using monounsaturated fats, low carb diet, whereas APOE 2 carriers suit a high fat low carb diet, regardless of the saturated fats.
It appears that the effects of these genes are dose dependant. For example, the cholesterol levels of an APOE 2 / APOE 3 are naturally relatively low, whereas the APOE4 / APOE4 gene makeup is associated with a greater risk of high cholesterol.
One study shows that APOE4 carriers have up to 20 times greater risk of developing Alzheimer’s disease that non carriers. A full list of specific circumstances can be found here.
I recently had my genes tested, and I am a mix of APOE 3 and APOE 4, which means I might be better suited to a Mediterranean diet that utilises a little more monounsaturated fats.
As usual, I am not a doctor. I am purely writing about what I find in my research and from other reliable sources. If you are in doubt about what to do, you should always seek medical advice.