‘Clean Eating’ is the concept that we should eat foods which are as unprocessed as possible. For example, a baked potato is less processed than french fries, a homemade granola bar is less processed than a store bought one, whole wheat flour is less processed than white flour. The goal behind clean eating is to be leaner, ie. to reduce overall body fat (while retaining muscle mass), or to gain muscle with less fat gain.
Why Clean Eating Works
Avoiding 'fast food', restaurant foods, and junk foods helps limit caloric intake as these foods tend to be high in fat and low in satiety. Cooking your own food means that errors in nutrition labels will not throw off your caloric deficit. Also, avoiding food cooking techniques which make it hard to estimate caloric content such as deep frying helps (deep fried foods are considered more processed). An increase in fresh produce and whole grains, and decrease in processed foods, can result in more energy. This is because high fat processed foods can make us feel sluggish, and high sugar processed foods can give us sugar crashes. More energy means better workouts.
Why Clean Eating Fails
Due to the rigid nature of the 'rules' of clean eating, individuals can become isolated from friends, family and co-workers by bringing their own food everywhere and refusing to eat in restaurants. Cooking everything from scratch is time consuming and may result in low diet compliance. Also, it is important to note that if you ate the same amounts of protein, fats, and carbohydrates of foods which are not clean, you would get the same results in your physique (provided your workouts are the same of course)!
How to Fix the Concept of Clean Eating
Replace clean eating with healthy eating, and make some new less rigid rules. Limit the amount of processed foods but don't give them up completely. For example, have a couple slices of store bought whole wheat bread, but use homemade chicken breast in your sandwich. Allow yourself to go to restaurants. You can develop strategies to not completely ruin your diet while eating out. For example, it is helpful to look at the nutrition information online ahead of time. You can also look for meals labelled Weight Watchers, or simply "use your head" when deciding what will be good/bad to choose - ie. something with cream sauce is probably high in calories. Another good way to be flexible is to take 10% of your caloric intake and have whatever the heck you want.
One way to summarize this discussion is to admit that, despite its flawed theoretical basis, “clean eating” is a concise short-hand that encapsulates many good dietary practices, while noting that zealous adherence to any such set of strict, arbitrary diet rules is not necessary.
Healthy Eating Basics
'Healthy Eating' involves making food choices that we feel will have a positive effect on our health. The USDA recommendations for healthy eating are [Dietary Guidelines for Americans, 2010]:
- Limit calorie intake to the amount needed to attain or maintain a healthy weight for adults, and for appropriate weight gain in children and adolescents.
- Consume foods from all food groups in nutrient-dense forms and in recommended amounts.
- Reduce intake of solid fats (major sources of saturated and trans fatty acids).
- Replace solid fats with oils (major sources of polyunsaturated and monounsaturated fatty acids) when possible.
- Reduce intake of added sugars.
- Reduce intake of refined grains and replace some refined grains with whole grains.
- Reduce intake of sodium (major component of salt).
- If consumed, limit alcohol intake to moderate levels.
- Increase intake of vegetables and fruits.
- Increase intake of whole grains.
- Increase intake of milk and milk products and replace whole milk and full-fat milk products with fat-free or low-fat choices to reduce solid fat intake.
- Increase seafood intake by replacing some meat or poultry with seafood.
Healthy Eating Science
Let’s look at several different components of a healthy diet, and develop a set of positive motivations that are scientifically supported.
Choose a high fiber diet (25-35g/day)
- A high fiber diet (at least 24g/day) may reduce your risk of colorectal cancer [Dahm et al].
- A diet high in soluble fiber, such as in oatmeal, peas, and beans, may lower LDL (‘bad cholesterol’). [Brown et al]
- A diet high in insoluble fiber (whole grain wheat, nuts, vegetable/fruit skins) can keep your bowel movements regular and prevent hemorrhoids.
- A diet high in soluble fiber, such as psyllium and oatmeal, can alleviate symptoms of irritable bowel syndrome. [Bijkerk et al]
- Soluble fiber helps normalize blood glucose levels by slowing the rate at which food leaves the stomach and by delaying the absorption of glucose following a meal. [Mcintosh and Miller, Bolton et al; Ray et al]
- Foods that are high in fiber tend to be less energy dense while keeping you fuller longer (delayed gastric emptying) and can help you stick to your caloric goals while dieting. [Ray et al]
Limit simple sugars
- Foods that contain high amounts of processed sugars (eg. soda, candy) are often lacking in micronutrients.
- High sugar diets, specifically those high in fructose, result in high triglyceride levels which is a risk factor for heart disease. [ Teff et al; Bantle]
- High carbohydrate diets also raise triglyceride levels [Appel et al]. By lowering sugars from ‘empty calorie’ foods, we can lower overall carbohydrates.
Limit sodium intake (≤ 2300 mg)
- Reduced sodium intake decreases blood pressure.[Vollmer et al, Bray et al]
Reduce trans fatty acids
- Trans fats cause LDL levels to rise and HDL levels to decrease, which means a poor LDL/HDL ratio, and increased coronary heart disease risk. [Mensink and Katan; Willet et al]
Eat fruits and vegetables
- They are full of micronutrients - eat a ‘rainbow’ of colors to get the widest spectrum of vitamins/minerals.
- They help keep you full longer due to fiber content.
- Fruit can help satisfy sugar cravings without supplying a large dose of sugar.
Eat whole grains
- They supply more micronutrients than their ‘white’ counterparts.
- They are a source of soluble fiber (eg. oatmeal) and/or insoluble fiber (eg. wheat).
Eat dairy products
- Calcium and dairy have been shown to aid with fat loss. [Zemel et al]
- Calcium combined with weight bearing exercise can have beneficial effects on bone mineral density. [Specker]
Eat peanuts, tree nuts and/or seeds
- They have high amounts of vitamin E, zinc, and other minerals; as well as omega-3.
- They are a good source of fiber.
Eat more fish (2 servings of fatty fish per week)
- Omega-3 fatty acids have been shown to reduce the incidence of cardiovascular disease.[Kris-Etherton et al]
- Dietary guidelines for Americans, 2015-2020. USDA, US Dept of Health and Human Services.
- Dahm et al. Dietary Fiber and Colorectal Cancer Risk: A Nested Case–Control Study Using Food Diaries.JNCI J Natl Cancer Inst (2010) 102 (9): 614-626.
- Brown et al. Cholesterol-lowering effects of dietary fiber: a meta-analysis. Am J Clin Nutr 1999;69:30–42.
- Bijkerk et al. Soluble or insoluble fibre in irritable bowel syndrome in primary care? Randomised placebo controlled trial. BMJ 2009;339:b3154
- Bolton et al. The role of dietary fiber in satiety, glucose, and insulin: studies with fruit and fruit juice. Am J Clin Nutr February 1981 vol. 34 no. 2 211-217
- Ray et al. Long-term effects of dietary fiber on glucose tolerance and gastric emptying in noninsulin-dependent diabetic patients. Am J Clin Nutr March 1983 vol. 37 no. 3 376-381
- McIntosh M, Miller C. A diet containing food rich in soluble and insoluble fiber improves glycemic control and reduces hyperlipidemia among patients with type 2 diabetes mellitus. Nutr Rev 2001 Feb;59(2):52-5 2001.
- Zemel et al. Calcium and Dairy Acceleration of Weight and Fat Loss during Energy Restriction in Obese Adults. Obesity Research (2004) 12, 582–590
- Specker, B. L. Evidence for an interaction between calcium intake and physical activity on changes in bone mineral density. Journal of Bone and Mineral Research. Volume 11, Issue 10, pages 1539–1544, October 1996
- Appel et al. Effects of Protein, Monounsaturated Fat, and Carbohydrate Intake on Blood Pressure and Serum Lipids. JAMA. 2005;294(19):2455-2464.
- Teff et al. Dietary Fructose Reduces Circulating Insulin and Leptin, Attenuates Postprandial Suppression of Ghrelin, and Increases Triglycerides in Women. The Journal of Clinical Endocrinology & Metabolism June 1, 2004 vol. 89 no. 6 2963-2972
- Bantle. Dietary Fructose and Metabolic Syndrome and Diabetes. J. Nutr. June 2009 vol. 139 no. 6 1263S-1268S
- Mensink and Katan. Effect of Dietary trans Fatty Acids on High-Density and Low-Density Lipoprotein Cholesterol Levels in Healthy Subjects. N Engl J Med 1990; 323:439-445
- Willet et al. Intake of trans fatty acids and risk of coronary heart disease among women. The Lancet Volume 341, Issue 8845, 6 March 1993, Pages 581–585
- Vollmer et al. Effects of Diet and Sodium Intake on Blood Pressure: Subgroup Analysis of the DASH-Sodium Trial. Annals of Internal Medicine. December 18, 2001 vol. 135 no. 12 1019-1028
- Bray et al. A further subgroup analysis of the effects of the DASH diet and three dietary sodium levels on blood pressure: results of the DASH-Sodium Trial. The American journal of cardiology 15 July 2004 (volume 94 issue 2 Pages 222-227)
- Kris-Etherton et al. AHA Scientific Statement. Fish Consumption, Fish Oil, Omega-3 Fatty Acids, and Cardiovascular Disease. Circulation. 2002; 106: 2747-2757.