As a long distance runner, weight is very important to me. Imagine carrying an extra 2kg’s during an Ultra Marathon, that’s like carrying an extra 2 litres of water that I never intended to drink. That’s just crazy. You wouldn’t do it! So you can understand most people’s confusion when I tell them I eat a relatively high fat diet. I always hear things like, “Your mad!” “What about the weight gain?” (I’m 185cm and 70kg’s and have eaten this way for 10 years) and also the big one… “Aren’t you concerned about cholesterol or heart disease?” Well of course I am concerned about them; that’s one of the main reasons I started educating myself on nutrition about 10 years ago. It was around the time I lost my Father to to a number of conditions relating to type 2 diabetes and heart disease. He was a kind of negative motivator to me. I didn’t want to end up like him.
So yes, I eat fat. And I eat plenty of it from a number of sources. Coconut oil, butter, cod liver oil, fatty cuts of meat, avocados, olives etc. There are a variety of fat sources available, some considered bad fats and some considered good fats. Yet they are all important sources of nutrients and believe it or not, they are a great source of energy.
In endurance athletes, up to 80% of our energy comes from fats, not carbohydrates like we are more commonly told. Sure, if we hit a big hill, and sprint up it completely anaerobically, we switch over to carbohydrates as the dominant fuel, but for most of us mid pack runners, staying aerobic and conserving our energy, especially up hills, is the wisest choice. Avoiding dietary fat actually reduces our ability to tap into our fat resources. Also we can carry far more energy in fat than we can in carbohydrate.
Fat comes under the heading of a Macro Nutrient. Macro meaning large, Nutrient meaning something that in the absence of, causes sickness, disease or death. The other Macro Nutrients are Carbohydrates and Proteins. Fat is really our preferred source of energy and a major factor in many processes in the body. Here are just a few:
- Our cells walls are reliant upon fat and cholesterol to make them soft, flexible and strong
- Cholesterol is a precursor to our sex hormones, testosterone in men, progesterone and estrogen in women. It also helps produce our steroid hormones
- The insulation known as the myelin sheath on our nerves is predominantly cholesterol
- Without fat, our body can’t store fat soluble vitamins like vitamin A, D and E
- Cholesterol is a major part of the healing process in the body. After major surgery, your cholesterol levels skyrocket temporarily
- Cholesterol is needed for proper function of serotonin receptors in the brain. Serotonin is the body’s natural “feel-good” chemical
Cholesterol is always a topic that comes up in conversation when I talk about fat. Dietary cholesterol has very little, if any, effect on blood cholesterol levels. The reason for this is the fact that only 15%, depending on your diet, of your cholesterol, comes from your diet. The rest is manufactured by the body. You eat less cholesterol, your body produces more, and vice versa. As far as heart disease is concerned, it really has no correlation to cholesterol either, with half the people suffering heart attacks having higher than average cholesterol, with the other half being on the lower than average side. What is more important than overall level is the HDL (good cholesterol) to LDL (bad cholesterol) ratio. Although there is no good and bad cholesterol as both are necessary to our bodies function.
Here is a out take from a study done into the effects of dietary cholesterol from eggs on blood cholesterol.
“Cholesterol feeding studies demonstrate that dietary cholesterol increases both LDL and HDL cholesterol with little change in the LDL:HDL ratio. Addition of 100 mg cholesterol per day to the diet increases total cholesterol with a 1.9 mg/dL increase in LDL cholesterol and a 0.4 mg/dL increase in HDL cholesterol. On average, the LDL:HDL ratio change per 100 mg/day change in dietary cholesterol is from 2.60 to 2.61, which would be predicted to have little effect on heart disease risk. These data help explain the epidemiological studies showing that dietary cholesterol is not related to coronary heart disease incidence or mortality across or within populations.”
So if saturated fat and cholesterol have no effect on heart disease, what does? The simple answer is inflammation. Inflammation caused by high blood sugar levels and trans-fats. In our highly processed diet, with so many starches and carbohydrates, our blood sugar is always getting high. As athletes, we are told to eat plenty of carbohydrates as we need them for fuel. This is partly true. We can top them up during a long run; we can also replenish them after a run or gym session, that’s fine. Your body is designed to handle that. But eating high carb foods right through the day, because we need the energy for tomorrow morning’s run is a big mistake. We store sugar in our bodies as glycogen. Glycogen is stored in our muscles, organs and blood cells. Places where it is readily available for a quick burst of energy. Think about our ancestors who had to run fast to get away from imminent danger just to survive. But once we have enough on board, we really struggle to store any more. Even if you carb load, the extra amount you gain is minimal.
All this extra energy you are taking in as sugar is stressing the body. Firstly the extra sugar is floating around through your blood and causing damage to your arteries in the form of inflammation. You are also putting extra load on your pancreas by producing tons of insulin to process it (this eventually leads to insulin resistance, a precursor of type 2 diabetes) and the only thing your body can do with it all is store it as fat. Next time you eat low fat, think about that. More on this next week when I discuss sugars and the flaws of the glycemic index.
So which are the good fats and which are the bad fats?
- Processed fats like vegetable oils are quite unstable. Once heated they oxidise rapidly and become damaged. Fats that contain cholesterol, are actually quite stable and handle high heats with the cholesterol being a strong anti oxidant.
- Margarine’s are the worst of the bunch. Also known as hydrogenated fats, they are processed in a manner that converts them into a molecule that is very closely related to plastic. This is not new information. In the 1960’s a book was released called “Margarine, the plastic fat and your heart disease”, yet this information only became widely accepted in the last 5 years or so. Margarine’s are full of Trans Fatty Acids and cause inflammation just like the excess sugar I just spoke about. They are a huge factor in heart disease.
- Pure butter, not the commercial stuff, but made from raw dairy is an excellent food. It is actually very high in vitamin K which has been shown to help weight loss.
- Coconut oil, one of the healthiest fats around is a medium chain triglyceride (a saturated fat) which stimulates the thyroid gland. Low thyroid is a cause of weight gain in many people. This is one of the most heat stable fats around. Along with other fruits like avocado and olives, these are a great source of fat.
- Lard is one of the best sources of dietary vitamin D and is also great for cooking at high temperatures.
- Cod liver oil is known mostly for its EPA and DHA omega 3’s, but is also one of the richest sources of vitamin D and dietary cholesterol. Far more cholesterol than lard!
- Flax seed oils and plant source omega 3’s area a bit of a waste of time. They are ALA omega 3’s which our body can’t really use. They need to be converted to EPA and DHA which we really struggle to do. The conversion rate can be as low as 3-5%. Plus the fact that it can oxidize at room temperature, it is really not worth the risk.
- Olive oils are OK as long as they are relatively fresh and only used for low heat purposes such as frying fish. Never use for red meats where the cooking temperature is generally higher.
These are just a few fats which can be of harm or benefit to you, especially as a runner. The thing you should take from this is avoid all processed fats as our bodies are not designed to process these. The natural fats, which Mother Nature has provided for us and we have all been told to avoid, are the ones to eat. The human race evolved eating these fats and our bodies have adapted very well to handle them. What we can’t handle is something that comes from a science lab.
Maybe this post has not been directly about running, but following this advice and including some good fats in your diet can help reduce some inflammation you get from training hard. The less inflammation you have, the quicker you can recover and get out for your next session. Also one of the reasons I got into running was for health. If you are the same, don’t take my word for it, look up these topics yourself and make an educated decision. There are so many mis-truths out there regarding health. We really need to educate ourselves to get the most out of our bodies.
P.S. If this has been of interest to you, or you know of anyone with high cholesterol, had a heart attack or on cholesterol lowering medication, I urge you to look into Dr Dwight Lundell’s book “The Cholesterol Lie”. There is some bad press around this guy, but from what I can see, it’s mainly because he is challenging the common beliefs of the medical industry. This will always get you bad press. The truth is though, he is a heart surgeon with over 5,000 surgeries under his belt and has realized in the last 10 years that the approach to heart disease by the medical industry is completely wrong.
Please forward this page onto anyone you know that may benefit from this information.