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Conversation with the nutritional wizard Part three
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Conversation with the Nutritional Wizard Part 3
By jamie Hale
Conversation between myself and Lyle McDonald
Click here to read part two http://www.maxcondition.com/page.php?83
Click here to read part one http://www.maxcondition.com/page.php?73
Jh: the bottom of page 135 it is indicated the fat intake should be kept relatively low during carb up phase to minimize fat gain. I am assuming that h fat has little effect on glycogen supercomp, but can also increase fat storage of dietary fat is too high.
Lm: Correct. At the same time, empirically some folks have noted better carb-ups with a small amount of fat, especially olive oil (monounsaturates). I have no idea why. But it's mainly to avoid fat regain during the carb-load.
Jh: My assumption would also be to limit fiber intake particularly greens etc the first half of carb up, but include more fiber the second half as this will slow down absorption of nutrients
Lm: And that was Dan's basic approach in Bodyopus, as you may recall. You started with very high GI liquid carbs and moved to lower GI/less refined/higher fiber carbs as it proceeded. I don't know that it honestly makes a huge difference but it does make sense to do it that way.
Jh: would it be safe to suggest between 104-144 gms of carbohydrates are required to support brain glucose needs?
Lm: I've seen anywhere from 100-120 listed as an average. I don't think it's worth getting that hung up about.
Jh: I am going to mention effects of exercise and glycogen loading speaking of enzyme regulation we spoke about in brief how would you word best in terms of glyc supercomp to moderately educated audience?
Lm: I'd probably try and point out that, when muscular glycogen stores are depleted, there are a host of adaptations in enzyme levels and carbohydrate utilization that ensure that incoming carbs go to refill glycogen. You might point out that, with glycogen depletion, even in the face of incoming carbs, the body continues to use fat for fuel (carbs going to glycogen). Even in the face of high insulin.
Because someone is going to ask you the following "Should I still do post-workout carbs on a diet, won't it impair my fat loss/I read in Body for Life that I should wait an hour to eat after I workout so I don't mess up fat loss." And you can tell them "Actually, the body will continue to use fat for fuel even in the face of carbs. And it's more important to stimulate recovery than to try to burn a few grams of extra fat (which get
burned anyhow)" I can send you the reference on that if you want it.
But I think that basically tells them what they need to know without overwhelming them with information.
Jh: when glycogen depleted will it be possible to fructose to be stored in muscle? My studies suggest muscle lacks an enzyme to store or convert fructose to glucose. Do these conditions change due to exercise? or will fruit still be preferred by the liver?
Lm: Fructose can't ever be stored by muscle, like you said, the muscle lacks the enzyme. At best, fructose will go to the liver, be converted to glucose and released immediately to the bloodstream to be stored as muscle glycogen that way
Jh: have you found particular diet regimens to be more successful in dealing with diabetes that others I think we briefly spoke of this
Lm: In general, lowering the glycemic load and increasing the proportion of monounsaturated fat (some papers go up to 40%) seems to be best. Unfortunately, you can't just jack up protein because, in diabetics, protein causes a pretty serious insulin response. E even there, some recent papers are using higher protein diets and finding better glcyemic control.
As I think I mentioned to you, some researchers prefer to keep carbs high but with a lower GI and studies do show a difference between keeping carb intake constant but lowering GI and lowering total carbs in terms of a few parameters. One of them is insulin sensitivity, diets where carbs are lowered in amounts tend to show an increase in blood FFA (durr) and a worsening of insulin sensitivity. But, ultimately, if carbs are low, who cares. And if it helps the person get rid of bodyfat, that will improve things.
The biggest (theoretical) argument against higher fat intakes is that weight/fat gain might occur because of the increased fat intake. as long as calories are controlled, this isn't any big deal.
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Jh: it is fairly accepted that whey is a faster acting protein than casein if they are both hydroslyates wouldn’t the comparable time release be relatively the same ratio
Lm: that's my feeling yes. Casein hydrosylate seems silly to me, it would seem to defeat the entire purpose of using casein in the first place.
Jh: what would be general insulin level measurements during ketosis ?
Lm: Page 39 Although some mention is made in the discussions below of the adaptations seen during this time period, most of the major adaptations to ketosis start to occur by the third day, continuing for at least 3 weeks (4-6). During the first 3 days of fasting, blood glucose drops from normal levels of 80-120 mg/dl to roughly 65-75 mg/dl. Insulin drops from 40-50 ºU/ml to 7-10 ºU/ml (5,7,8). Both remain constant for the duration of the fast. One thing to note is that the body strives to maintain near-normal blood glucose levels even under conditions of total fasting (5). The popularly held belief that ketosis will not occur until blood glucose falls to 50 mg/dl is incorrect. Additionally, the popular belief that there is no insulin present on a ketogenic diet is incorrect (7). One difference between fasting and a ketogenic diet is that the slight insulin response to dietary protein will cause blood glucose to be maintained at a slightly higher level, approximately 80-85 mg/dl (1). This most likely occurs due to the conversion of dietary protein to glucose in the liver.
Jh: what w3ould it be generally with a mixed diet?
Lm: A lot higher
On the fiber issue, my text (Biochemical and PHysiological Aspects of Human nutrition) states
"A leading researcher in this area of energy contribution from dietary fiber has assigned a value of 6 kg/g (1.44 kcal/g) for nonstarch polysaccharides and 8.4 kj/g (2.01 kcal/g) for resistant starches
(Livesy,2005), compared with 16.7 kj/g (4 kcal/g) for starch".
Comparison of high-fat and high-protein diets with a high-carbohydrate diet in insulin-resistant obese women.
McAuley KA, Hopkins CM, Smith KJ, McLay RT, Williams SM, Taylor RW, Mann JI.
Edgar National Centre for Diabetes Research, Medical and Surgical Sciences, University of Otago, PO Box 56, Dunedin, New Zealand.
-email-
AIMS/HYPOTHESIS: A diet low in saturated fatty acids and rich in whole grains, vegetables and fruit is recommended in order to reduce the risk of obesity, cardiovascular disease and type 2 diabetes mellitus. However there is widespread interest in high-fat ("Atkins Diet") and high-protein ("Zone Diet") alternatives to the conventional high-carbohydrate, high-fibre approach. We report on a randomized trial that compared these two alternative approaches with a conventional diet in overweight insulin-resistant women. METHODS:Ninety-six normoglycaemic, insulin-resistant women (BMI >27 kg/m(2)) were randomized to one of three dietary interventions: a high-carbohydrate, high-fibre (HC) diet, the high-fat (HF) Atkins Diet, or the high-protein (HP) Zone Diet. The experimental approach
was designed to mimic what might be achieved in clinical practice: the recommendations involved advice concerning food choices and were not prescriptive in terms of total energy. There were supervised weight loss and weight maintenance phases (8 weeks each), but there was no contact between the research team and the participants during the final 8 weeks of the study. Outcome was assessed in terms of body composition and indicators of cardiovascular and diabetes risk.
RESULTS: Body weight, waist circumference, triglycerides and insulin levels decreased with all three diets but, apart from insulin, the reductions were significantly greater in the HF and HP groups than in the HC group. These observations suggest that the popular diets reduced insulin resistance to a greater extent than the standard dietary advice did. When compared with the HC diet, the HF and HP diets were shown to produce significantly (p<0.01) greater reductions in several parameters, including weight loss (HF -2.8 kg, HP -2.7 kg), waist circumference (HF -3.5 cm, HP -2.7 cm) and triglycerides (HF
-0.30 mmol/l, HP [corrected] -0.22 mmol/l). LDL cholesterol decreased in individuals on the HC and HP diets, but tended to fluctuate in those on the HF diet to the extent that overall levels were significantly lower in the HP group than in the HF group (-0.28 mmol/l, 95% CI 0.04-0.52, p=0.02). Of those on the HF diet, 25% showed a >10% increase in LDL cholesterol, whereas this occurred in only 13% of subjects on the HC diet and 3% of those on the HP diet. CONCLUSIONS/INTERPRETATION: In routine practice a
reduced-carbohydrate, higher protein diet may be the most appropriate overall approach to reducing the risk of cardiovascular disease and type 2 diabetes. To achieve similar benefits on a HC diet, it may be necessary to increase fibre-rich whole grains, legumes, vegetables and fruits, and to reduce saturated fatty acids to a greater extent than
appears to be achieved by implementing current guidelines. The HF approach appears successful for weight loss in the short term, but lipid levels should be monitored. The potential deleterious effects of the diet in the long term remain a concern.
Jh: info i read today. your thoughts While to amount of carb required to avid ketosis is very small (about 50 g/ day) Do they mean ketourina ?
Technically, any diet with less than 100 grams of carbs will develop ketosis (in terms of blood concentrations, ketonemia) to one degree or another. I doubt you'd see urinary ketone excretion at that level. At 50 grams, you'd still have to develop some level of ketones to cover brain energy requirements. But you do see a rather large decrease in the need for gluconeogenesis at that level. Why I suggested 50 g/day in the
UD2.
Jh: what carbs are essential (didn’t know any were, this was a comment from my girlfriend’s nutrition teacher) ? are they referring to phytochemicals? generally i have understood carbs to not be essential due to the bodies ability to convert other substances to glucose. I have read a few things lately indicating carbs to be essential. Are they technically essential in any form?
Lm: Have to understand the definition of an essential nutrients
1. lack of it leads to death
2. can't be made by the body
By that definition, even phytochemicals are not essential. You will not die for lack of intake. Neither is fiber. You may be healthier for the intake of such, but you will not die without them. You will die for lack of certain amino acids, B12 or any of the vitamins/minerals. Dietary carbohydrates as a source of glucose are not essential because of #2, the body can generally make enough to cover needs from other sources. even carbs as a source of phytonutrients/fiber are not essential because you don’t die without them.
Jh: have you noticed a lowered lactate threshold or decrease in anaerobic performance if a meal that is highly acetic was consumed close to workout time
Lm: I don’t know that a single meal would have that much of an impact. I saw it suggested in a paper (I may have the PDF, I'll have to check) that several days on a more basic type of diet (less meat, more veggies) might help by increasing buffering capacity. Certainly, low carb diets, by increasing acid load tend to affect things negatively.
Jh: any studies you have ran across indicating lowered lactate threshold with lactofermentation or highly acetic foods?
Lm: Never seen it studied acutely but never paid attention, I'll see if I can track anything down.
Here's the abstract of the paper I"m thinking of, dunno if I have the PDF though
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Sports Med. 2003;33(8):615-31. Related Articles, Links
Dairy products, meat and sports performance.
Fogelholm M.
The UKK Institute for Health Promotion Research, Tampere, Finland. -email-
Creatine supplementation improves repetitive, short-term performance. It has not been shown that exclusion of meat from the diet would impair repetitive short-term performance. In contrast, reduction of protein intake and a concomitant increase of carbohydrate intake during a period of 3-5 days improves anaerobic (2-7 minutes) performance. The protein intake in a mixed or lacto-vegetarian diet is adequate even for elite athletes, providing that energy requirements are met. Many dietary supplements have been suggested to increase muscle mass and/or to decrease fat mass. Although the effects of conjugated linoleic acid on body composition in athletes are not clear, some positive findings in untrained, obese individuals call for more studies. Strenuous training may impair immune function and increase the susceptibility to infections. Exclusion of meat from the diet does not seem to have adverse effects on immune function. Glutamine supplementation (>3-6 g/day) may improve immune function, but more studies are needed. Similarly, more studies on the possible effects of whey protein and probiotic supplementation on immune function and performance in physically highly active individuals are warranted. Vitamin and mineral balance are not usually a problem among athletes. Notable exceptions may be calcium and iron in some females. Increased calcium intake in athletes with hormonal and menstrual disturbances could theoretically help in maintaining bone status; however, no data are available. A diet with meat may help in maintaining adequate iron stores.
Coming Soon
Protein: the complete guide
by Lyle McDonald and Jamie Hale
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