Remarkable clinical trial results appear relevant to weight control
You’ve probably heard that skipping breakfast is a bad idea.
Aside from leaving your brain starved for fuel until lunch, skipping breakfast has long been thought to lead to overeating later, and eventual weight gain.
Back in 2013, University of Alabama researchers published their review of 92 clinical studies that tested the weight gain or loss effects of skipping breakfast or eating various kinds of breakfasts.
The Alabama team found insufficient high-quality clinical evidence to pin the blame for obesity either on skipping breakfast or on choosing one kind of breakfast over another.
However, there is some clinical evidence linking big, fatty, and high-protein breakfasts to desirable metabolic outcomes, such as better weight and blood-sugar control.
For more than that, browse the articles listed at the end of this report.
Along the same lines, a new study from the University of Alabama at Birmingham found distinct metabolic benefits from eating breakfasts that were relatively high in fat, and low in carbohydrates.
Let’s examine the results of that clinical trial and place them into context.
Alabama clinical trial sees fat-burning benefit from fatty breakfasts
The University of Alabama at Birmingham conducts a lot of weight control research, including laboratory and clinical studies on the effects of breakfast.
And their latest clinical trial generated some intriguing insights into the fat-burning effects of breakfasts that provide different proportions of fat and carbs.
Led by nutrition researcher Nikki C. Bush, the Alabama team conducted a 4-week clinical trial designed to test the effects of high-fat versus high-carb breakfasts that contained equal proportions of protein (Bush NC et al. 2018).
According to the authors, theirs was the first ever study to test the hypothesis that eating specific ratios of fat and carbs at breakfast can affect fat-burning throughout the day.
They recruited 29 sedentary men and women aged 55 to 75, and randomly assigned them one of two groups:
- High-fat breakfast — 35% carbohydrates, 20% protein, 45% fat.
- High-carb breakfast — 60% carbohydrates, 20% protein, 20% fat.
Those assigned to the high-fat breakfast group ate one or more whole eggs five days per week.
Eggs were chosen because they’re easy to prepare and would allow the researchers to easily adjust the fat and protein content of breakfast, by varying the number of eggs consumed in relation to carbohydrate foods.
Importantly, to be sure the trial results were valid, all the breakfast foods were provided to the participants in both groups.
The participants were also assigned to eat “metabolically neutral” lunch and dinner meals in which carbohydrate, protein, and fat provided 50%, 20%, and 30% of calories, respectively.
Both groups were given individualized 7-day breakfast/lunch/dinner menu plans — to reflect each person’s calorie requirements (measured at the outset of the trial) — and instructions on how to prepare the meals.
After four weeks, the results showed that high-fat breakfasts sparked the burning of body fat, versus high-carb breakfasts.
The study’s authors put it this way: “The data from this investigation provide evidence that a high-fat breakfast results in higher fat oxidation [burning] over the next 24 hours.”.
Fat-burning is one key to achieving and maintaining weight loss and preventing accumulation of inflammation-generating belly fat.
As the authors wrote, “impairment of fat oxidation [burning] is associated with weight gain and insulin resistance.”
Skipping breakfast also raises fat burning rates, because the body isn’t given any calories after its night-long fast.
But clinical research shows that it triggers metabolic changes, which — if sustained by habitual breakfast-skipping — tend to raise diabetes risks.
What kind of fat is best for promoting fat burning?
There isn’t a clear answer to that very important question, at least when it comes to the difference between saturated, polyunsaturated, and monounsaturated fats as general types of fat.
Of course, the individual fats within each of those broad families can differ pretty widely in their effects.
Different saturated fats exert very different effects on our blood cholesterol levels and profiles, while the two basic families of polyunsaturated fats — omega-6 and omega-3 — differ in their effects, as do the individual omega-6 and omega-3 fats.
Among polyunsaturated fats, seafood-source omega-3s appear best at promoting fat burning — which is just one reason why fish-rich diets make a good deal of sense. But few Americans eat enough fish to get as much metabolic benefit as they could.
Australian researchers found that a breakfast high in monounsaturated fat beat a breakfast high in saturated fat — with the amount of fat burning rising in tandem with a person’s proportion of abdominal body fat (Piers LS et al. 2002)
More recently, Texas Tech University scientists found no variation in fat-burning rates among obese women in response to the basic kinds of dietary fat — saturated, polyunsaturated, and monounsaturated (Clevenger HC et al. 2015).
For some of our past coverage of the health effects of various breakfast strategies, see Fat for Breakfast May Deter Diabetes, Do Big Breakfasts Win for Weight Control?, High-Protein Breakfast Helps Blood Sugar Control, and Protein for Breakfast Allays Appetites All Day.
- Baum JI, Gray M, Binns A. Breakfasts Higher in Protein Increase Postprandial Energy Expenditure, Increase Fat Oxidation, and Reduce Hunger in Overweight Children from 8 to 12 Years of Age. J Nutr. 2015 Oct;145(10):2229-35. doi: 10.3945/jn.115.214551. Epub 2015 Aug 12.
- Bush NC, Resuehr HES, Goree LL, Locher JL, Bray MS, Soleymani T, Gower BA. A High-Fat Compared with a High-Carbohydrate Breakfast Enhances 24-Hour Fat Oxidation in Older Adults. J Nutr. 2018 Feb 1;148(2):220-226. doi: 10.1093/jn/nxx040.
- Clevenger HC, Stevenson JL, Cooper JA. Metabolic responses to dietary fatty acids in obese women. Physiol Behav. 2015 Feb;139:73-9. doi: 10.1016/j.physbeh.2014.11.022. Epub 2014 Nov 13.
- Dhurandhar EJ, Dawson J, Alcorn A, Larsen LH, Thomas EA, Cardel M, Bourland AC, Astrup A, St-Onge MP, Hill JO, Apovian CM, Shikany JM, Allison DB. The effectiveness of breakfast recommendations on weight loss: a randomized controlled trial. Am J Clin Nutr. 2014 Aug;100(2):507-13. doi: 10.3945/ajcn.114.089573. Epub 2014 Jun 4.
- Díaz EO, Galgani JE, Aguirre CA, Atwater IJ, Burrows R. Effect of glycemic index on whole-body substrate oxidation in obese women. Int J Obes (Lond). 2005 Jan;29(1):108-14. Erratum in: Int J Obes Relat Metab Disord. 2005 Jul;29(7):879.
- Meng H, Matthan NR, Ausman LM, Lichtenstein AH. Effect of prior meal macronutrient composition on postprandial glycemic responses and glycemic index and glycemic load value determinations. Am J Clin Nutr. 2017 Nov;106(5):1246-1256. doi: 10.3945/ajcn.117.162727. Epub 2017 Sep 13.
- Nas A, Mirza N, Hägele F, Kahlhöfer J, Keller J, Rising R, Kufer TA, Bosy-Westphal A. Impact of breakfast skipping compared with dinner skipping on regulation of energy balance and metabolic risk. Am J Clin Nutr. 2017 Jun;105(6):1351-1361. doi: 10.3945/ajcn.116.151332. Epub 2017 May 10.
- Park YM, Heden TD, Liu Y, Nyhoff LM, Thyfault JP, Leidy HJ, Kanaley JA. A high-protein breakfast induces greater insulin and glucose-dependent insulinotropic peptide responses to a subsequent lunch meal in individuals with type 2 diabetes. J Nutr. 2015 Mar;145(3):452-8. doi: 10.3945/jn.114.202549. Epub 2014 Dec 24.
- Piers LS, Walker KZ, Stoney RM, Soares MJ, O'Dea K. The influence of the type of dietary fat on postprandial fat oxidation rates: monounsaturated (olive oil) vs saturated fat (cream). Int J Obes Relat Metab Disord. 2002 Jun;26(6):814-21.