Some more intermittent fasting research

via Science Daily

In a paper published May 17 in Cell Metabolism, scientists from Salk's Regulatory Biology Laboratory reported that mice limited to eating during an 8-hour period are healthier than mice that eat freely throughout the day, regardless of the quality and content of their diet. The study sought to determine whether obesity and metabolic diseases result from a high-fat diet or from disruption of metabolic cycles.

The abstract is at Time-Restricted Feeding without Reducing Caloric Intake Prevents Metabolic Diseases in Mice Fed a High-Fat Diet

Chronic Cardio is healthy?

In our little paleosphere endurance exercise is usually characterised as a "bad" thing.  Mark Sission's Chronic Cardio post is the usual basis for all this, but there are other references too.  In general I agree with this view.  However sometimes other bits and pieces pop up that indicate a different viewpoint.  I saw this one the other day:

Autophagy-related and autophagy-regulatory genes are induced in human muscle after ultraendurance exercise

The purpose of this study was to evaluate whether ultra endurance exercise changes the mRNA levels of the autophagy-related and autophagy-regulatory genes. Eight men (44 ± 1 years, range: 38–50 years) took part in a 200-km running race. The average running time was 28 h 03 min ± 2 h 01 min (range: 22 h 15 min–35 h 04 min). A muscle sample was taken from the vastus lateralis 2 weeks prior to the race and 3 h after arrival. Gene expression was assessed by RT-qPCR. Transcript levels of autophagy-related genes were increased by 49% for ATG4b (P = 0.025), 57% for ATG12 (P = 0.013), 286% for Gabarapl1 (P = 0.008) and 103% for LC3b (P = 0.011). The lysosomal enzyme cathepsin L mRNA was upregulated by 123% (P = 0.003). Similarly, transcript levels of the autophagy-regulatory genes BNIP3 and BNIP3l were both increased by 113% (P = 0.031 and P = 0.007, respectively). Since upregulation of these genes has been related with an increased autophagic flux in various models, our results strongly suggest that autophagy is activated in response to ultra endurance exercise.

Autophagy is usually presented as a "good thing" - the self eating process by which cells clean themselves up, getting rid of waste products and some pathogens.  Often it is promoted by fasting and again in the paleo world it is one of the benefits that are claimed for intermittent fasting.  I've probably written about that in the past somewhere.

Anyway, this study seems to link it to ultraendurance exercise.....actually it is talking epigenetics as far as I can see, particular autophagy related genes being switched on.  I suppose this might make sense if the exercise has actually cause massive damage and the body is frantically trying to clear up and repair the mess.  Maybe not so positive.

How to lose body-fat healthily.

Previous blog posts have been about Carbohydrates, Fats & Proteins. However, when you go shopping, you buy food. So this blog post is going to be about food. Updated!

1) If you're eating a high-carb diet, eat 6 small meals or 3 meals and 3 snacks per day to keep your blood glucose relatively stable. I used to believe that it also kept your metabolic rate high, but I now know this to be a myth. If you're the type of person who gets lowish blood glucose in the mornings (which may make you ravenously hungry and therefore highly likely to buy junk food when you're away from home), skipping breakfast is not advisable. If you're the type of person who isn't satisfied by small meals/snacks, a small number of large meals (Intermittent Fasting) is a better option.

2) Meals and snacks should contain proteins, fats and fibrous carbs.

3) Slow sugary/starchy carbs can be eaten in meals/snacks at breakfast and before/after workouts/exercise/intense activity. If/when you are sedentary, keep slow sugary/starchy carbs to a minimum. Keep fast sugary/starchy carbs to a minimum (except for the occasional treat or post-workout) as they can cause large fluctuations in blood glucose and insulin levels. The more intense exercise you do, the more slow sugary/starchy carbs you can eat.

4) Drink >1.5 litres of no-added-sugar watery drinks per day. If your urine is darker than straw, drink more. If you're weeing too often, drink less.

5) Balance your omega-6 and omega-3 essential fatty acids (EFAs) by eating about 100g of omega-3 rich oily fish (sild, sardines, pilchards, mackerel, herring, salmon, trout, fresh tuna etc) per day or supplement with fish oil capsules such that you get at least 2g of EPA+DHA per day. Please note that tinned tuna contains virtually zero omega-3 fat.
If you're vegetarian or vegan, eat 25g (women) or 50g ( men) of powdered linseeds (a.k.a. flaxseeds) per day with lots of fluids or supplement with flaxseed oil in bottles/capsules such that you get at least 10g (women) or 20g (men) of flaxseed oil per day.

6) Eat 2 to 3 portions of low-sugar fruits per day - preferably before meals/snacks. Minimise your consumption of high-sugar fruits.

Proteins are:- Meats, poultry, fish, eggs, cheese, Quorn, seeds, nuts, legumes (peas, beans & lentils).

Fibrous carbs are:- All vegetables that grow above ground level, bulbs (onions, leeks, garlic etc) and "vegetable" fruits (tomatoes, peppers, cucumbers/courgettes, aubergines, avocados, olives etc).

Slow sugary/starchy carbs are:- All-bran, no-added-sugar muesli, oats, sweet potatoes, lightly-boiled new potatoes eaten hot, cold or refrigerated, Basmati rice, non-overcooked legumes & root veggies, lumpy wholegrain rye breads, Burgen/Vogel's soya & linseed breads.

Fast sugary/starchy carbs are:- White wheat breads, wholemeal wheat breads, most breakfast cereals including Shredded Wheat, Weetabix, Cheerios, Grapenuts etc, sugar, sweets, chocolate, cakes, biscuits, cereal bars, sweetcorn, overcooked tubers e.g. jacket potatoes, overcooked root veggies, overcooked legumes e.g. baked beans.

High sugar fruits are:- Ripe & over-ripe bananas, grapes, pineapples, sweet apples, sweet pears, sultanas, raisins, currants and any dried fruits with added sugar.

Low sugar fruits are:- Berries, stone fruits, citrus, Granny Smith apples, Conference pears. Dried apple rings, apricots, pear halves, peach halves and prunes without added sugar are high in sugar but they release that sugar very slowly.

Fats are sats, monos and the EFAs mentioned above. Butter is high in sats and monos. Olive oil & spreads are high in monos. Sunflower/safflower/corn oils & spreads are very high in omega-6 EFAs - minimise your consumption of these. Don't fry or roast with high-EFA oils as they oxidise and convert into trans-fats too quickly. Meats contain sats, monos and some EFAs. Minimise your consumption of anything with the word "hydrogenated" in the ingredients list.

Some foods fall in-between categories like yellow bananas which are medium speed sugary/starchy carbs. Green bananas are slow carbs and black bananas are fast carbs.

Depending on your insulin sensitivity, speed of metabolism and exercise levels, you may get away with eating fast sugary/starchy carbs - you'll just have to "suck it and see".

One final bijou tip-ette:- Avoid walking down "dodgy" supermarket aisles (confectionery, cereals, booze, fizzy drinks) as "What the eye don't see, the heart don't grieve over".

Happy New Year folks!

Cont'd on How to lose body-fat healthily, Part 2.