GOOD FATS & BAD FATS – Science or Supposition?
Why follow science if science keeps changing? Because, when science is based on objectively measured phenomena that appear to solve a problem consistently, what more could we want?
ANSWER: The realization that science is relative and that marketing, fashion and vested interests dilute the truth even more than statistics.
Now that the horse has bolted with the message that carbs are the killer not fats, the next obvious question that arises is which fats are good and which are bad, to supply up to 40% of a healthy diet. Current science offers a spectrum of conclusions.
- Mono unsaturated oils are the best and virgin or extra virgin olive oil- a kernel of the Mediterranean Diet, has withstood the test of time, particularly used on salad or added to food after cooking.
- Coconut, grape seed and avocado oils are good for high heat cooking since they are not easily oxidized at higher temperatures.
- Positively unhealthy are the poly unsaturated ones, like corn, canola, sunflower and soy. They are often made with GMOs which are subjected to large amounts of toxic chemical sprays; when heated they break down and release harmful free radicals and they are often tainted with petroleum solvents such as hexane. Cold pressed canola is less problematic.
Until recently regarded as the bad guys, but it turns out, only due to years of poor deductive reasoning on the part of doctors and manipulative interests of governments and drug companies.
- Butter is good, particularly organic and from grass fed herds.
- Eggs are great.
- Avocados are greater still.
- Seeds (particularly cold stored flax or chia seeds) and nuts, especially brazil nuts are healthy, but high in calories and easy to binge on.
- Fatty meat, especially organic and grass fed chicken, turkey and beef are currently on the OK list, but the jury is still out on this.
- Dairy is better low fat or small amounts of full fat (calories are the issue here) than non fat.
- Fatty fish such as wild halibut, salmon, sardines and mackerel are the best source of combined animal protein and fats you could wish for.
Fats release leptin in the body and leptin suppresses hunger. Eat too little fat or too much carbohydrate and you will have constant sugar spikes and a desire to eat more.
The desirable end result of fat metabolism is the correct ratio of high density lipoproteins (HDL), low density lipoproteins (LDL) and triglycerides . The last are worst and the first are best. Syndrome X ( high BP, high blood sugar, high incidence of diabetes and excess fat) is associated with high triglycerides and low HDL. Reversing that ratio makes sense.
In a healthy diet a little fat goes a long way and excessive fat intake, even of the good fats, will increase body weight, whereas reasonable amounts to achieve satiety and balanced diet, currently lead the pack in supporting optimal heart, brain and energy health.
Dr Ruth Rabinowitz MB BCh.