Fructose: alcohol without the buzz

From an article in Advances in Nutrition by Robert Lustig (lightly edited). The author argues that high fructose consumption can lead to typically alcohol related diseases such as diabetes and fatty liver disease, even in children. Here are some extracts:

What do the Atkins Diet and the traditional Japanese diet have in common? The Atkins Diet is low in carbohydrate and usually high in fat; the Japanese diet is high in carbohydrate and usually low in fat. Yet both work to promote weight loss. One commonality of both diets is that they both eliminate the monosaccharide fructose. Sucrose (table sugar) and its synthetic sister high fructose corn syrup consist of 2 molecules, glucose and fructose.

Glucose is the molecule that when polymerized forms starch, which has a high glycemic index, generates an insulin response, and is not particularly sweet. Fructose is found in fruit, does not generate an insulin response, and is very sweet. Fructose consumption has increased worldwide, paralleling the obesity and chronic metabolic disease pandemic.

Sugar (i.e., fructose-containing mixtures) has been vilified by nutritionists for ages as a source of “empty calories,” no different from any other empty calorie. However, fructose is unlike glucose. In the hypercaloric glycogen-replete state, intermediary metabolites from fructose metabolism overwhelm hepatic mitochondrial capacity, which promotes de novo lipogenesis and leads to hepatic insulin resistance, which drives chronic metabolic disease. [ie too much fructose leads to liver overload resulting in fat production and insulin resistance]

Fructose also promotes reactive oxygen species formation, which leads to cellular dysfunction and ageing, and promotes changes in the brain’s reward system, which drives excessive consumption. Thus, fructose can exert detrimental health effects beyond its calories and in ways that mimic those of ethanol, its metabolic cousin. Indeed, the only distinction is that because fructose is not metabolized in the central nervous system, it does not exert the acute neuronal depression experienced by those imbibing ethanol. These metabolic and hedonic analogies argue that fructose should be thought of as “alcohol without the buzz.”

Article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3649103/

Currently, per capita consumption of fructose or fructose-containing sugars is at ∼130 lb/y (almost 60 kg/y) for the average American. UK figures are lower. "According to the NHS, British people eat 700g of sugar a week" - that would be 36 kg/y, but not all of that would be fructose. A lot (most?) of this sugar is found in UPF, added to make it more desirable and hence more profitable.

Metabolism: see diagrams below and compare Inflammation (JNK1) onwards in both ethanol (alcohol) and fructose:

Should there be a "units of sugar per week" recommendation like there is for alcohol?

Fat Cells

So recently I've been reading about fat cells, also known as adipocytes and occasionally as lipocytes. In many ways they are like standard human cells, having many (if not all?) of the same components: nucleus, ribosomes, mitochondria etc.

But they differ in substantial ways. They do not divide, there is no cell division. They live for about 10 years. They grow or shrink in size as fat is absorbed or released. We have a more or less constant number of fat cells. About 10% die each year and are replaced. 

Fat is released from the cells and into the blood stream through lipolysis; triglycerides are converted into glycerol and free fatty acids. Lipolysis is used to mobilise stored energy during fasting or exercise. The most important regulatory hormone (amongst many, including epinephrine) in lipolysis is insulin; lipolysis can only occur when insulin action falls to low levels, as occurs during fasting.

So how to burn belly fat? Exercise and fast.

I will look at how fat is created (lipogenesis)  in a future article.

Waist measurement: a better tool than BMI?

First of all, what is BMI? It stands for Body Mass Index. It's a calculation based on your weight and your height. The NHS has a calculator here. It is used by the NHS and UK doctors to determine if you have a weight problem. Values between 18.5 and 25 are OK, 25 - 30 is overweight, and 30+ is obese. 

This link is to an NPR article with 10 reasons why BMI is flawed. Flaw number 3 is here:

It [BMI] makes no allowance for the relative proportions of bone, muscle and fat in the body. But bone is denser than muscle and twice as dense as fat, so a person with strong bones, good muscle tone and low fat will have a high BMI. Thus, athletes and fit, health-conscious movie stars who work out a lot tend to find themselves classified as overweight or even obese.

My BMI is 21.4, supposedly healthy but the British Heart Foundation (BHF) has other ideas...

BHF advocates waist measurement as a better method of determining if you have unhealthy body fat, in particular visceral fat (fat around your internal organs like heart, kidneys, pancreas etc). There is a BHF calculator here, based on waist measurement (at one inch above navel, breathing out), gender, and ethnicity. My healthy waist size would be 37 inches or less but is in fact 39 inches (although I wear 34 inch jeans), resulting in the following warning:

You're at risk

Your waist measurement means that your weight could be affecting your health, and you're at higher risk of developing heart and circulatory diseases, and conditions such as Type 2 diabetes. Keeping to a healthy weight and carrying less fat around your middle will help to keep your heart healthy. We recommend that you check your BMI too, to find out if you're a healthy weight for your height.

So the NHS says I'm healthy ("Your result suggests you are a healthy weight") and at the same time the BHF says I'm at risk. I'm going with the BHF here and aiming to reduce my waist size to 36.5 inches. I'll keep you posted.

PS I went for a blood test at my GP's surgery this week. The nurse measured my blood pressure and my weight. I asked if they ever measure waist size. Apparently not; she said she'd look into it. My blood pressure looks like this:

PPS: Here's what a high risk waist measurement (44 inches) looks like:

PPPS: I didn't have a tape measure but found one on eBay, delivered within a few days, cost £1.09 including postage. How do they do that? It's less than a first class stamp...

Thoughts on Intermittent Fasting

Introduction:

Intermittent fasting (IF) is promoted as a way to reduce weight, reduce belly fat and to detox your body. There are many ways to do it, including...

Time restricted eating, eg fast for 14 hours then eat between 8 am and 6 pm, a 10 hour window, also known as 14:10. My personal habit is a 9 hour window from 11 am to 8 pm, so 15:9. This sometimes extends to 10 pm...

One meal a day (OMAD) is a 23:1 system, ie one hour per day for eating, 23 hours for fasting. Sounds brutal to me...

Extended fasting, eg 24 hours or 36 hours without food. Drinks allowed are water, black coffee, tea without milk (I like green tea or peppermint tea). I do a 36 hour fast each week from Monday 8 pm to Wednesday 8 am. I seem to be reducing weight at about one pound per week using this method combined with a 9 hour eating window on other days.

Alternate day fasting (ADF): fast one day, eat the next. This is essentially a 36 hour fast every other day with a 12 hour eating window. For sample results, see:

I Lost 165 Pounds Using Alternate Day Fasting

Alternate day fasting - modified (ADFM): Same as ADF but with one 500 calorie meal on "fasting" days.

5:2 fasting: a variant on ADFM with 5 days of normal eating, 2 days (eg Tuesday and Friday) with only one 500 calorie meal.

Some words from Robert Lustig:

Intermittent fasting (IF) is a less painful way [than calorie restriction] of jacking up the same subcellular processes. By depriving your liver of calories for fourteen to sixteen hours per day, IF gives it a chance to activate AMP-kinase, suppress mTOR, increase autophagy, chew up some of the liver fat that's been stored, improve insulin resistance, and lower your insulin - the same outcomes that low-carb and ketogenic diets achieve. IF has also been shown to promote weight loss, blood glucose control, reduced inflammation, improvements in memory and stress resistance, slowed ageing, and longer life span. Each of these benefits is a manifestation of improvement in insulin sensitivity. In this way, your leptin won't drop so fast that you feel awful; and since insulin blocks leptin signalling, the lower your insulin levels go, the better your brain can see the leptin. This means your sympathetic nervous ratchets up, and you burn faster. All in all, most people find IF easier to adhere to long-term, and it's better for you.

~ Metabolical, page 209

[text captured on my phone using Google Lens - love it!]

Recent dietary changes

 I have made several changes to my diet recently.

• dairy-free
• for animal welfare reasons, not health
• almond milk at home, oat milk at cafes, restaurants etc
• Applewood vegan cheese (tried Cathedral City, hated it)
• yogurt: tried Lidl's Vemondo vegan yogurt, too chemical tasting so now zero
• butter: now using Vitalite (not as tasty)
• replaced Camembert with hummus on morning crackers
• no pizza!
• added flax oil omega-3 and calcium supplements (already taking one-a-day multi-vit and multi-mineral supplements)
• coleslaw
• replaced with sauerkraut and carrots (from Tesco's Polish section)
• eggs
• replaced medium free range eggs with large, for extra protein
• bread
• about to replace wholegrain bread with rye bread (more fibre, less sugar)
• rice
• changed portion size from 125 g to 80 g (reduce carbs)
• mushrooms
• changed from canned (now very expensive) to frozen
• cauliflower cheese bakes/veggie fingers
• switched to oven roasted broccoli and cauliflower (from frozen)
• breakfast
• no longer eating breakfast
• salsa
• Lidl's salsa seems to be free from emulsifiers, preservatives etc but home made tastes better
• unchanged
• baked beans, fish fingers, salami, dry roasted nuts, olives, garlic, eating out twice a week (fish and chips; poached eggs on avo toast)
• intermittent fasting
• nine hour eating window, 11 am to 8 pm (15:9)
• 36 hour fast Monday 8 pm to Wednesday 8 am

Conclusion: a work-in-progress; my energy levels are fine, even on a 36 hour fast day. I seem to be losing weight at about one pound per week (21st June: 11st 12.25lb; 27th July: 11st 7.75lb). Waist measurement is 39 inches, hoping to reduce it to 36.5. The goal however is not weight loss but reduced belly fat. And a healthier, dairy-free diet.