less sugar show longer life?

[johndela1]

These links seem to support eating less sugar to live longer. This makes me wonder if eating a lot of fruit and/or sugar is a good thing.

http://www.ncbi.nlm.nih.gov/pubmed/16000018
http://www.pubmedcentral.nih.gov/articl ... 0020231-b8
http://www.lef.org/dsnews/ds_letter_2007_feb.htm#1

[RRM]

From this first link:

http://www.ncbi.nlm.nih.gov/pubmed/16000018

Reduction of either dietary yeast or sugar can reduce mortality and extend life span, but by an amount that is unrelated to the calorie content of the food, and with yeast having a much greater effect per calorie than does sugar. Calorie intake is therefore not the key factor in the reduction of mortality rate by DR in this species

So, in the Drosophila (fruit-fly), restricting yeast intake increases lifespan more than restricting sugar intake.
They therefore conclude that calorie intake is not the key factor in this species.
They do not at all conclude that sugar is, rather than energy. No, yeast rather than energy.
So, yeast intake has greater adverse effects than energy intake.
Right?

http://www.pubmedcentral.nih.gov/articl ... 0020231-b8

the authors examined life span in fruit flies (Drosophila melanogaster) fed one of four different diets: (1) a combination of yeast and sugar (control), (2) restricted in yeast only, (3) restricted in sugar only, and (4) restricted in yeast and sugar. The authors observed that in the restricted sugar group, as compared to the controls, maximal life span was unchanged and median life span was increased by only 12%. On the other hand, both maximal and median life spans were increased substantially in the restricted yeast group and in the restricted yeast and sugar group (Figure 1). Importantly, the authors claim that total calorie contents of the restricted sugar and restricted yeast diets were similar. Thus, from this study it can be implied that restricting carbohydrate is less advantageous than restricting protein/lipid for mediating the effects of dietary restriction (DR) on life span.

So, restricting only sugar had minimal positive effects.
Restricting yeast had much greater effects.
And, restricting protein / fat is more effective than restricting sugars.

http://www.lef.org/dsnews/ds_letter_2007_feb.htm#1

"In the usual CR diet, all sources of calories (carbohydrate, proteins, and fat) are restricted
...
"A new rat study of caloric restriction .... breaks new ground by using a diet in which fat calories and protein calories are the same in the restricted diet as for the ad libitum-fed rats; only carbohydrates (sucrose and cornstarch) are restricted. The beneficial results reported are very exciting because they point to an emphasis on a reduced-carbohydrate but high-protein (as a percentage of calories) diet for better long-term health.
...
maintaining protein intake significantly reduced the negative impact of an “all calories restricted” diet on muscle protein synthesis"

So, instead of giving them too little protein (rodent food normally is nutrient dense), now they dont.
Of course taking in too little protein goes at the expense of your muscles; no news here.
And of course, if you take in less energy (sugars, in this case), there are positive effects on lifespan.
And yes, if you dont eat too little protein, thats healthier.

Sugars are the only pure source of energy. Protein and fats are also required for (re)construction purposes. So, what better way to restrict calory intake than by reducing the intake of sugars?

Conclusion: its not about replacing sugars by protein and/or fats.
Its about restricting calories, but taking in sufficient protein and essential fats (and vitamins etc)
So, if you want to increase your lifespan, the first choice to make is:
Are you willing to restrict your calorie intake?
If so, then reduce your calorie intake to such an extend that you still take in enough protein and essential fats.

[johndela1]

So are you saying that the best macro nutrient to reduce is carbohydrate?

And that protein and fat are more essential?

[RRM]

So are you saying that the best macro nutrient to reduce is carbohydrate?

No.

And that protein and fat are more essential?

No.

IF you want to reduce your calorie intake, THEN its best not to reduce your protein and fat intake below requirement levels. The same is true for carbs, though that just applies to energy, as to how energetic you want to
(still) feel.
IF you want to reduce your calorie intake, then it depends on how much protein, fat and carbs you are consuming and how energetic you want to feel; as to which nutrient you need to reduce first.
Glucose is not at all less essential. In fact, directly, its most essential. But for (re)construction purposes its not required at all, indeed.
We need all those nutrients.
Depening on what you want, and on how you want to feel, and on what you eat, you can reduce the intake of specific nutrients.

[johndela1]

I've read in lo carb books that you can live with out dietary carbs but now with out fat or protein. This makes it sound like carbs are not the most critical thing. Maybe, not understanding, but it seems that carbs are a source of fuel and fat is also that. Can't fat take the place of carbs?

[RRM]

I've read in lo carb books that you can live with out dietary carbs but now with out fat or protein.

Thats because proteins and specific fats supply essential structural components.

This makes it sound like carbs are not the most critical thing.

You can perfectly live a long life without love, so love is not the most critical thing, right? But its also what gives life meaning. To me, love is THE most critical thing to life.
Yes, you can live without carbs, but carbs give your life energy and feeling well, because glucose is the main source of energy for the brain and sugars most effectively feed your brain and muscles with energy.

carbs are a source of fuel and fat is also that. Can't fat take the place of carbs?

Why would you want to decrease the quality of your life?
Your body is best when its in balance. Why not feed it that what it needs for energy; both sugar like molecules and fat-like molecules? They have different effects on the metabolism of a number of neurotransmitters that greatly influence how well we feel.

[Christina]

I agree, that feeling happy, full of love and also desire is the greatest pleasure of life. Quality rather than quantity. Even if I lived longer, eating a certain way, I would never sacrifice those aspects. As an example, there are so many vegan raw foodist, too, who really believe in their diet but the lack of nutrients makes them less luscious and sexual/joyfull and more"spiritual". At least that happened to my husband when he tried the raw vegan way. It just seems like too little pleasure to me.