Sugar and the Insulin Response - in plain, simple English
A friend asked me to explain the whole sugar-insulin response thing.
So, to answer that question, I searched for some good explanations online, to send my friend links, but I couldn’t find any really straight-forward writing, so I thought I would write it myself!!
I am purposefully over-simplifying this here and keeping any kind of ‘science talk’ out, or to a minimum.
In short, layman’s terms, it goes like this:
You eat food with sugars (or carbohydrates) in the food, they go through the stomach and reach the duodenum, where the pancreas senses that there is sugar present, and releases insulin into your system. Other receptors in your blood notice the insulin, and it triggers an action which shifts the excess glucose (sugar) to fat stores - I.E. those excess sugars are stored in fat deposits as “future energy reserves”.
So, problem #1: if we keep eating loads of carbs and sugary food, we put on fat weight, because those excess sugars keep getting stored away as fat.
A one-way door
The ‘pathway’ in and out of a fat cell is like a one-way door, it can open to let energy in, or to let energy out, but it can’t be doing both those things at the same time. Now, when your pancreas releases insulin, various systems within the body read the signal that insulin is present, and your ‘body chemistry’ is set up to enable the transfer of glucose molecules into fat cells (stores). While your body chemistry is configured this way, the one-way door is open to let energy IN to fat cells, but not out. Therefore, when insulin is present in your blood (which happens for a while after each and every time you eat sugary food or carbohydrates, like processed grains) you can only store fat, not burn it. It is impossible to access fat stores (which represent a reservoir of stored energy) while insulin is circulating, and this creates problem #2: people who eat sugary foods or grain-based foods every few hours, almost permanently have an insulin response at play in their bodies, and hence their fat reserves are never tapped into for energy, because the ‘one way door’ is always open the wrong way, so again, they tend to gain fat weight.
A scenario such as this can be created when people eat highly processed cereal for breakfast, biscuits or chocolate snacks mid-morning, sandwiches on processed bread for lunch, more confectionery in the afternoon, pasta for dinner and sweets or chocolate in the evening. By consuming refined carbs or refined sugars every 2 or 3 hours from 7 in the morning til 9 or 10 in the evening, their bodies are in ‘insulin response mode’ all day long. In such a scenario, they never burn fat for energy, and so they are prone to gain weight and also to suffer fluctuating energy levels, due to the rising and falling blood sugar levels.
While on the subject of rising and falling blood sugar levels, this affects your energy levels. You need some sugar in your blood to give you ‘immediate’ energy, to keep you awake and keep your limbs moving and your brain working. The human diet did not include much sugar until recent times. For many, many thousands of years sugar was virtually unknown – there was no refined white sugar, no processed grains and much less fruit than we eat today, so broadly speaking, our bodies were designed to handle only small amounts of naturally occurring sugar.
When the pancreas senses a big hit of sugar has come into the digestive system, it injects a big hit of insulin into the blood, and the end result is that ALL the sugar is removed from the blood…resulting in an energy low, that weak ‘afternoon slump’ feeling we get, and those ‘sugar low’ feelings that make so many of us crave more sweet, sugary food. This is problem #3 – it’s a destructive cycle, energy lows and sugar cravings, which perpetuates round and round. See picture (kindly sent by a friend, thank you).
And what does it all lead to? It leads to what is called ‘reduced insulin sensitivity’. In a person who consumes a lot of refined carbohydrate foods (bread, cereal, pasta, spaghetti, etc.) and a lot of refined white sugar, the patterns described above repeat over and over again day after day for months and years. Every time the sugar comes in, the insulin is triggered, over and over again, and over time the body becomes de-sensitized to the effects of insulin, and it takes more and more insulin to do the job, and then eventually this leads to problem #4: Type 2 Diabetes - and many other chronic health problems.
Putting it all together, in simple terms, a diet high in refined sugar and processed grain foods, leads to:
- Easy fat/weight gain
- Persistent inability to burn off excess body fat
- Unstable energy levels; tiring energy lows; regular sugar cravings
- Diabetes (Type 2) and other serious long term chronic illness
There are some acceptable ‘carb choices’ - oat groats are not refined, and are digestible; parsnips, sweet potato, marrow, pumpkin, swede and squash all make good healthy substitutes for white potatoes; quinoa is the best rice substitute; and so there are plenty of better options available.
I was also asked, on this point: “So there are naturally occurring sugars in veggies, so should I avoid those if I am trying to achieve a fat-burning effect to lose weight?”
I answered -
Sugars and carbohydrate are roughly the same thing, but there are lots of different types. Generally, we tend to label simple sugars (fast burning) as “sugar” - that’s refined sugar in confectionery, cakes and sweets, etc., and also fruit sugar. Then we tend to label the complex sugars (slower burning) as “carbs” - that’s food like bread, pasta, rice, cereal, etc.
But actually, carbohydrates are also in other foods, most particularly vegetables.
Eating the ‘sugars’ (carbs) in vegetables, delivers those sugars to your blood slowly, because the glucose molecules are bound up in the fibre parts of the veg, which slows break-down, digestion and absorption, so eating vegetables does not produce that big insulin ‘hit’, the response to a big dose of refined sugar.
So eating lots of food that contains refined sugar will stop you burning fat as an energy source, and cause you to store the excess sugar as fat deposits. Eating vegetables will deliver healthy slow-burning sugars to your body at a slow enough rate that the rapid-insulin-response is minimized. The only veg that may stimulate an above-optimal insulin response would be excessive carrots, eaten alone without any other foods, or consumed as a juice. Carrots alone have a fairly high sugar content, but eaten combined with other foods as part of a balanced meal, they are fine.
If you are scientifically minded, or already knowledgeable on this topic, this post will bother you, it’s very simplified and it purposefully drops the lesser details, however, if you appreciate simplicity, then in short - cut the sugar, cut the stodgy carbs, and eat lots of fresh veg, and lean/clean protein, and you set up your system optimally for fat burning and to reduce long-term stress to your pancreas.