• Guest - w'd love to know what you think about the forum! Take the 2025 Survey »

Your thoughts on fructose

Mr_Pot said:
Sucrose (table sugar) is half glucose, half fructose, it is the type of sugar that comes from plants, notably sugar cane and sugar beet of course but also any fruit. I believe it is fructose that tastes sweet rather than glucose. I haven't tried this myself, perhaps someone who has dextrose tablets can confirm glucose is not sweet.
Click to expand...

I used Rapilose to do my home OGTT. It is supposed to be pure glucose. I can't say I found it very sweet.
 
Not a fan. It’s everything I don’t need. It causes temporary leptin resistance and reduces insulin sensitivity. That is its mechanistic role in nature for mammals...to aid in the creation of fat for winter. If I missed any of the foods that contain it then I would not completely avoid it, but I don’t, so I do :cool:
 
hankjam said:
which strikes me as odd.
Click to expand...

Yup! Your intuition is right. Eating whole-fruit, replete with fibre, water etc. which actually needs to be digested, is a different beast altogether. Same goes for whole starches, which we've also been eating for hundreds of thousands of years.
 
Just very so often, and if it agrees with my meter, I will have a bit of seasonal, local natural.
This week was half a perfectly ripe pear straight from a neighbours tree.

I am more liberal with berries as I grow a lot and they freeze well
 
MrsA2 said:
Just very so often, and if it agrees with my meter, I will have a bit of seasonal, local natural.
This week was half a perfectly ripe pear straight from a neighbours tree.

I am more liberal with berries as I grow a lot and they freeze well
Click to expand...

My neighbour has a stunning apple tree or three and for the last 30 years I walked past..... and never nicked one. This year, I asked and was given a whole bunch. Lovely in small amounts.
 
Jim Lahey said:
Not a fan. It’s everything I don’t need. It causes temporary leptin resistance and reduces insulin sensitivity. That is its mechanistic role in nature for mammals...to aid in the creation of fat for winter. If I missed any of the foods that contain it then I would not completely avoid it, but I don’t, so I do :cool:
Click to expand...

Is there a known mechanistic distinction between insulin causing fat gain in Winter, but not at other times?
 
Jim Lahey said:
Come again?
Click to expand...

Unless I am wrong, you suggested a mechanism that relied on insulin to fatten up mammals for Winter. I am asking what mechanism is in place to stop these same animals from getting fat during the other three seasons
 
I think the question was If insulin does not cause weight gain through the year, then what changes to make us put on fat in the winter?

For a start, in the older times, we became less active in the winter months, With home gyms and Pelatons that is perhaps not so important.

Secondly, with modern food storage and all round food availabiliy (perhaps not so well provided post covid?) then we no longer need to lay in fat for the winter. Note that the fat gain is in advance of winter and is triggered by Harvest Home and the pickling / jam making season. But many mamals overeat in this autumn so as to be able to reduce activity when the cold days come. Hedgehogs bears squirrels prepare for this, humans lay up food in storage and preserved foods instead. There is no specifiec mechanism involved apart from a tendancy to over eat the goodies from summer, intake of more frutose than usual (again not necessarily so in modern society) and slowing down the metabolism.

Those of us of older disposition may remember our grand parents doing the post harvet rituals of pickling, curing ham and bacon, drying fish and making fruit cakes. We may also remember Olive Oil being very expensive and not a common salad dressing. Salads used to have mainly vinegar only. Tallow and cod liver oils were not very helpful for this purpose and seed oils had not been invented in my early years. Sadly cod liver oil was plentiful YUK.

Nature controlled our fructose intake naturally by making these food sources seasonal. Mankind has resolved this problem and now we cn gorge on fruit all year round, thus potentially feeding the obesity crisis that we appear to be suffering now.
 
Beating-My-Betes said:
Unless I am wrong, you suggested a mechanism that relied on insulin to fatten up mammals for Winter. I am asking what mechanism is in place to stop these same animals from getting fat during the other three seasons
Click to expand...

Fructose is readily available in nature during the summer months. The temporary leptin and insulin resistance helps facilitate the creation of fat that is then used as a fuel source during the harder winter months. The obvious problem here is that not only is modern fruit bred to increase quantities of both glucose and fructose, but it’s also encouraged to be eaten 24/7/365.
 
Comparison with other mammals is pointless due to their diversity. Polar bears put on huge amounts of fat to see them through the winter but they are carnivores so don't get any fructose. Apes eat a lot of fruit but have very little body fat. Early man is thought to originate from equatorial Africa where they don't have winter.
 
Mr_Pot said:
Comparison with other mammals is pointless due to their diversity. Polar bears put on huge amounts of fat to see them through the winter but they are carnivores so don't get any fructose. Apes eat a lot of fruit but have very little body fat. Early man is thought to originate from equatorial Africa where they don't have winter.
Click to expand...

To be fair I don’t think anyone has claimed that you can’t get fat without fructose, but it does aid in the creation of fat owing to the way in which it is metabolised exclusively in the liver. This mechanism is fairly well understood in humans.
 
Mr_Pot said:
Comparison with other mammals is pointless due to their diversity. Polar bears put on huge amounts of fat to see them through the winter but they are carnivores so don't get any fructose. Apes eat a lot of fruit but have very little body fat. Early man is thought to originate from equatorial Africa where they don't have winter.
Click to expand...
How about Inuit?
 
Jim Lahey said:
Fructose is readily available in nature during the summer months. The temporary leptin and insulin resistance helps facilitate the creation of fat that is then used as a fuel source during the harder winter months. The obvious problem here is that not only is modern fruit bred to increase quantities of both glucose and fructose, but it’s also encouraged to be eaten 24/7/365.
Click to expand...

As Mr_Pot already mentioned, we likely started our global spread from places where fructose was available all year. Either way, looking at mechanisms without context, and without consideration for real-world, observable results, doesn't really make any sense. Knowing the mechanism by which our body stores fat tells us nothing without the other factors necessary to put said mechanism into action, which, in this case is energy excess.

This doesn't change, no matter how much fructose current fruit has, or how much it is recommended to eat (Not actually that much, relatively-speaking).
 
Beating-My-Betes said:
Unless I am wrong, you suggested a mechanism that relied on insulin to fatten up mammals for Winter. I am asking what mechanism is in place to stop these same animals from getting fat during the other three seasons
Click to expand...
the animals have a different food in the other three seasons.
 
Beating-My-Betes said:
This doesn't change, no matter how much fructose current fruit has, or how much it is recommended to eat (Not actually that much, relatively-speaking).
Click to expand...

It does. Fructose incrementally increases hepatic insulin resistance. It also blunts the actions of leptin. The former is likely to result in higher levels of circulating insulin required to deal with partitioning x amount of energy. The latter results in longer and more intense hunger. Both of these things are documented in humans. Alcohol has a very similar action.

But I suspect we won’t agree, which is fine. The thread is only asking for our thoughts after all.
 
lucylocket61 said:
the animals have a different food in the other three seasons.
Click to expand...

Can you give some examples of animals that eat completely differently in various seasons i.e only consume fructose in the late Summer.Autumn months?
 
Back
Top