Explanation of Dietary Guidelines
Rationale (ISSN Position Stand on Meal Frequency)
- Increasing meal frequency does not appear to favorably change body composition in sedentary populations.
- If protein levels are adequate, increasing meal frequency during periods of hypoenergetic dieting may preserve lean body mass in athletic populations.
- Increased meal frequency appears to have a positive effect on various blood markers of health, particularly LDL cholesterol, total cholesterol, and insulin.
- Increased meal frequency does not appear to significantly enhance diet induced thermogenesis, total energy expenditure or resting metabolic rate.
- Increasing meal frequency appears to help decrease hunger and improve appetite control.
La Bounty PM, Campbell BI, Wilson J, Galvan E, Berardi J, Kleiner SM, Kreider RB, Stout JR, Ziegenfuss T, Spano M, Smith A, Antonio J (2011). International Society of Sports Nutrition position stand: meal frequency. J Int Soc Sports Nutr.16, 8:4.
Eat a variety of foods
- Better ensures ingestion of all essential nutrients
- Decreases risk of developing food intolerances
Eat fruits or vegetables
- Source of vitamins, minerals, fiber, and phytonutrients
- May spare calcium and glutamine
Eat high fiber foods
- Less tendency to eat calorie dense foods
- By filling up on vegetables, fruits, beans, and whole grains
- Fiber can decrease the absorption of dietary fat
- Fiber acts a barrier in the intestines
- May help stabilize blood sugar levels
- Helps prevent constipation by adding mass to stool
- Also see fiber's other health benefits
Rationale for Moderate Fat
- Lower fat foods are less calorie dense
- Dietary fat may be more likely to convert to body fat than carbohydrates or protein
- May have lesser tendency to overeat
- Particularly if previous meal or snack is small or skipped
- Fat is more palatable
- Also see: Dietary Fat and Appetite Control
- Hydrogenated fat has been linked to increase risk of heart disease
- Most vegetable oils are high in Omega-6 Fatty Acids
- Promotes inflamation
- Early studies suggested saturated fat may be associated with Cardiovascular Disease and certain cancers
- See Lipid Hypothesis
- Dietary fat offers satiety
- Read Macronutrient Ratio Studies.
- In men, decrease in dietary fat content and an increase in the degree of unsaturation of fatty acids reduces the serum concentrations of androstenedione, testosterone and free testosterone (Hämäläinen 1984).
- Read Lipid Hypothesis counter argument.
Hämäläinen E, Adlercreutz H, Puska P, Pietinen P (1984). Diet and serum sex hormones in healthy men. J Steroid Biochem. 20(1):459-64.
Limit sugar consumption
- Chronic sugar consumption has been linked to obesity and metabolic syndrome
- See High Fructose Corn Syrup Q&A
- See Sugar: The Bitter Truth video seminar
- Can reduce appetite compared to low fat diet (Nikols-Richarson 2005, McClernon 2007)
- Possible greater reduction of abdominal fat as compared to low fat diet (Volek 2004)
- Lowered Triglycerides (Noakes 2006, Wood 2006, Brinkworth 2009)
- Increased HDL (Noakes 2006, Wood 2006, Brinkworth 2009)
- if fat is substituted for carbs
- Improvement of LDL when accompanied by weight loss (Wood 2006)
- Reduced VLDL and overall reduction and increased size of LDL
- More stabilized blood sugar and insulin levels (Noakes 2006)
- Improved symptoms of metabolic syndrome even without weight loss (Volek 2005)
Brinkworth GD, Noakes M, Buckley JD, Keogh JB, Clifton PM (2009). Long-term effects of a very-low-carbohydrate weight loss diet compared with an isocaloric low-fat diet after 12 mo. Am J Clin Nutr. 90(1):23-32.
McClernon FJ, Yancy WS Jr, Eberstein JA, Atkins RC, Westman EC (2007). The effects of a low-carbohydrate ketogenic diet and a low-fat diet on mood, hunger, and other self-reported symptoms. Obesity (Silver Spring). 15(1):182-7.
Nickols-Richardson SM, Coleman MD, Volpe JJ, Hosig KW (2005). Perceived hunger is lower and weight loss is greater in overweight premenopausal women consuming a low-carbohydrate/high-protein vs high-carbohydrate/low-fat diet. J Am Diet Assoc. 105(9):1433-7.
Noakes M, Foster PR, Keogh JB, James AP, Mamo JC, Clifton PM (2006). Comparison of isocaloric very low carbohydrate/high saturated fat and high carbohydrate/low saturated fat diets on body composition and cardiovascular risk. Nutr Metab (Lond). 11;3:7.
Volek JS, Feinman RD (2005). Carbohydrate restriction improves the features of Metabolic Syndrome. Metabolic Syndrome may be defined by the response to carbohydrate restriction. Nutr Metab (Lond). 16;2:31. doi: 10.1186/1743-7075-2-31.
Volek J, Sharman M, Gómez A, Judelson D, Rubin M, Watson G, Sokmen B, Silvestre R, French D, Kraemer W (2004). Comparison of energy-restricted very low-carbohydrate and low-fat diets on weight loss and body composition in overweight men and women. Nutr Metab (Lond). 8;1(1):13.
Wood RJ, Volek JS, Liu Y, Shachter NS, Contois JH, Fernandez ML (2006). Carbohydrate restriction alters lipoprotein metabolism by modifying VLDL, LDL, and HDL subfraction distribution and size in overweight men. J Nutr. 136(2):384-9.
- Improves post workout recovery (Niles 2001)
- Faster rate of muscle glycogen re-synthesis
- 50% more glycogen can be stored (Friedman 1991)
- Improved performance in subsequent exercise
- Less muscle damage
- Faster rate of muscle glycogen re-synthesis
- Increased protein synthesis
- Nearly 3 fold increase (Levenhagen 2001)
- Decreases post exercise cortisol levels
- Increase lean muscle mass (Esmarck 2001, Holm 2004)
- Decreases risk of injury (Flakoll 2004)
- Ingestion of sugar (glucose) has shown to acutely depress testosterone by 25% (Iranmanesh 2012, Caronia 2013).
Caronia LM, Dwyer AA, Hayden D, Amati F, Pitteloud N, Hayes FJ (2013). Abrupt decrease in serum testosterone levels after an oral glucose load in men: implications for screening for hypogonadism. Clin Endocrinol (Oxf). 78(2), 291-6
Iranmanesh A, Lawson D, Veldhuis JD (2012). Glucose ingestion acutely lowers pulsatile LH and basal testosterone secretion in men. Am J Physiol Endocrinol Metab. 302(6):E724-30.