Grandma's around the world chant a nursery rhyme to promote healthy eating:
"From the lips to the hips, the fat you eat is the fat you wear."
Those same grandmas that stuffed you with chocolate chips cookies knew right where those cookies would end up! — Or did they? It’s no surprise that when you are gaining fat, you are consuming beyond what your body needs. Yet, how our body uses the large food molecules, the proteins, carbohydrates and fats is not completely clear. Generally, carbohydrates are broken down into simpler sugars and stored as glycogen (1). Proteins are digested into amino acids and absorbed for a variety of uses from cell signaling to growing hair (1). Fats, made up of fatty acids, are absorbed easily and provide stored energy and insulation (1). Small fluctuations of the total carbohydrates, fats and proteins someone is eating tend to balance themselves over time. However, larger fluctuations and especially those eating more will result in more weight gain regardless if it is an extra serving of pasta or cake right?
To answer the above, scientists took their fancy scissors, grabbed some fat, and examined it. By then comparing it to the individual’s diet, a connection was found (4,5,6). For example, monounsaturated fatty acids, (think vegetable oils), made up the largest portion of total fatty acid in adipose (fat) tissue at 54% and also diet at 42% (5). They also found similar results for trans-fats and omega-3 fatty acids (4,5,6). This correlation is shown by comparing many recent scientific studies, but also differences that came up are from people being unreliable about self-reporting (4,6). There may also be differences between men and women depending on the type of fat people eat and the source of fat (animal vs. vegetables). In particular, many of the studies centered around men over eating carbohydrate (6,7). As with anything in the world of food and nutrition, Future more research is needed, perhaps in a metabolic ward where diet can be more strictly controlled.
This naturally brings another question: Should one consume less fat to lose fat?
This may result in weight loss, and more likely when coupled with exercise, but weight loss leans on many factors. One reason it may not is that even if carbohydrates may not be stored as fat, they still will provide energy and prevent the body from needing to use fat storage (5,7,8).
So, our grandmas may have known another secret: It is easier to never gain the weight in the first place!
Author: Amandeep (Andy) Bains
Edited by Renée Y. Chan, MS, RD, CDN
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