A Healthy Way to Eat for Breast Cancer Survivors

A plant-based, extra virgin olive oil diet, such as the traditional Mediterranean diet, has long been associated with a wide range of health benefits.

A diet rich in plant products is easy to prepare, healthy, and inexpensive compared to a diet that contains animal products. ¹ 

Below is a sample meal plan for a 1,500 calorie diet. You can use this meal plan as it is or make substitutions for different vegetables, fruits, and starches.

Breakfast
1 oz. (dry weight) breakfast cereal
2 tablespoons of nuts (almonds, pecans, or walnuts)
6 to 8 fluid oz. of milk
2 servings of fruit (a serving is ½ cup or about ½ piece)

Lunch
Potato salad:
- 8 oz. (dry weight) chopped and boiled potatoes
- 2 cups of chopped vegetables (whatever is seasonal)
- 2 tablespoons of extra virgin olive oil
- Optional: capers, herbs – fresh or dry
1 serving of fruit

Dinner
2 tablespoons of extra virgin olive oil
3 cups chopped fresh or frozen vegetables
1 cup cooked rice (preferably brown rice)
Optional: herbs and sauces such as hot sauce, hoisin, etc.

Cook the vegetables into the extra virgin olive oil until desired tenderness.  Add the cooked rice and heat through.

References

1. Flynn M, Schiff, AR. Economical healthy diets (2012): Included lean animal protein costs more than using extra virgin olive oil. J Hunger & Environmental Nutrition 2015;10:467-82.

A primarily plant-based diet includes vegetables, fruits, and foods in the starch group (pasta, rice, potatoes, bread, and legumes). Animal products (meat, poultry, and seafood) are either excluded or included only in small amounts.  

A plant-based diet emphasizes foods that will improve your health and minimizes foods that will not improve your health or that studies suggest may increase your risk of disease.

Plant-based foods include:

• Vegetables
• Fruits
• Foods in the starch group, including pasta and flour-based foods like bread and rice 
• Other grains such as barley, quinoa, and potatoes
• Legumes (beans)

The traditional plant-based Mediterranean diet includes daily servings of extra virgin olive oil and has long been associated with a wide range of health benefits. Phytonutrients, found in all plant products, have been shown to be the reason plant-based diets are healthy.

Importance of Fiber

Prior to about 1990, it was commonly thought that the fiber content of plants leads to health benefits. As all plant products contain it, a high-fiber diet may also be one high in plant products. By definition, fiber is a carbohydrate that we do not digest. However, there are two types of dietary fiber – soluble and insoluble – and they have different functions in our body.

Soluble Fiber

Soluble fiber will dissolve in water and create a gel, resulting in the “mucky” texture found when water is added to oat bran cereal. Foods that can be made into a jam or jelly like berries tend to contain soluble fibers. When we eat soluble fiber, it can trap nutrients like glucose, cholesterol, and minerals in the small intestine and slow down their absorption. 

Insoluble Fiber

Insoluble fiber does not dissolve in water. It provides structure in food, like the bran found in whole grains. In our small intestine, insoluble fiber can trap water, increasing the size of the waste material and making it easier to pass through your intestines. This leads to better bowel function and decreases the risk of constipation. Breakfast cereals with a fiber content of at least nine grams per serving are most effective for preventing constipation. 

If you are interested in plant-based eating, try switching some meals to vegetarian and eating animal foods less often or in smaller amounts. For example, if you currently eat animal protein at both lunch and dinner, try preparing some plant-based lunches. You don’t need to become a vegetarian or vegan, but the more plant-based meals you eat, the better for your health. 

Our sample meal plan  can show you how to prepare a plant-based meal.

You do not actually need animal foods for protein — vegans, or people who do not eat any animal foods, can get enough protein in their diet. Our daily need for protein is not very high, and when you eat more protein than you need in a day, the extra can be converted to fat and result in a higher body weight. 

The amount of protein we need each day is actually smaller than what is portrayed in the media. Protein is found in both vegetables and starch (pasta, rice, potatoes, bread, and legumes), so including these food groups in your diet will likely mean you are eating enough protein. 

By adding animal protein to your meals (meat, poultry, seafood, dairy, and eggs), you are likely exceeding your protein needs for the day. While we can store carbohydrates as glycoge and fat as fat, protein is not stored as anything related to protein. In fact, the protein we eat is digested to amino acids, which is what we absorb. Any amino acids not needed for protein function in the body are broken down, converted to fat, and then added to our fat stores. 

More and more studies have shown that eating a diet with higher protein than is needed is related to a higher body weight/ body fat content.^1-9 Try to include some plant-based meals during the week, or at least try to have only one meal a day that contains poultry, seafood, or meat and make the other meals vegetarian. 

References

1. Gunther AL, Remer T, Kroke A, Buyken AE. Early protein intake and later obesity risk: which protein sources at which time points throughout infancy and childhood are important for body mass index and body fat percentage at 7 y of age? Am J Clin Nutr. 2007;86(6):1765-1772.
2. Koppes LL, Boon N, Nooyens AC, van Mechelen W, Saris WH. Macronutrient distribution over a period of 23 years in relation to energy intake and body fatness. Br J Nutr. 2009;101(1):108-115.
3. McCarty MF. The origins of western obesity: a role for animal protein? Med Hypotheses. 2000;54(3):488-494.
4. Murtaugh MA, Herrick JS, Sweeney C, et al. Diet composition and risk of overweight and obesity in women living in the southwestern United States. J Am Diet Assoc. 2007;107(8):1311-1321.
5. Raatz SK, Conrad Z, Johnson LK, Picklo MJ, Jahns L. Relationship of the Reported Intakes of Fat and Fatty Acids to Body Weight in US Adults. Nutrients. 2017;9(5).
6. Shay CM, Van Horn L, Stamler J, et al. Food and nutrient intakes and their associations with lower BMI in middle-aged US adults: the International Study of Macro-/Micronutrients and Blood Pressure (INTERMAP). Am J Clin Nutr. 96(3):483-491.
7. Thedford K, Raj S. A vegetarian diet for weight management. J Am Diet Assoc.111(6):816-818.
8. Vinknes KJ, de Vogel S, Elshorbagy AK, et al. Dietary intake of protein is positively associated with percent body fat in middle-aged and older adults. J Nutr.141(3):440-446.
9. Virtanen HEK, Koskinen TT, Voutilainen S, et al. Intake of different dietary proteins and risk of type 2 diabetes in men: the Kuopio Ischaemic Heart Disease Risk Factor Study. Br J Nutr. 2017;117(6):882-893.

It’s a good idea to limit your red meat/ beef intake. Eating beef, especially that has been cooked to a char, on a weekly basis has been linked to an increased risk of breast cancer. Frequent consumption of red meat (mainly beef, which includes steak and ground beef products like hamburger, meatloaf, and meatballs) and processed meat (cold cuts, bacon, and sausage) increases the risk of many chronic diseases, including breast cancer.^1-4 There are several possible reasons for this, but it does not seem to be due to beef’s total or saturated fat content.

Beef contains a specific polyunsaturated fat, arachidonic acid, which has been shown to promote tumor growth⁵ and increase DNA damage by oxidation⁶. Some of the amino acids that make up beef’s protein can stimulate insulin secretion,⁷ and higher insulin levels in blood have been linked to a greater risk of breast cancer.⁸ 

Beef seems to be especially harmful when cooked with high, dry heat, such as grilling. The black/ charred part has compounds called heterocyclic amines (HCAs), shown to act like nicotine — they can start the damage that leads to both cancer and heart disease. Specific to breast cancer, HCAs have been shown in an animal model to stimulate the growth of mammary tumors.⁹ A study of American women showed that those who consistently ate charred meat had a much greater risk of developing breast cancer compared to those who ate meat that was not charred.¹⁰ If you eat beef, try not to eat it too often. When you do have it, try to prepare it so it is not heavily charred. 

References

1. Farvid MS, Sidahmed E, Spence ND, Mante Angua K, Rosner BA, Barnett JB. Consumption of red meat and processed meat and cancer incidence: a systematic review and meta-analysis of prospective studies. Eur J Epidemiol 2021;36:937-51.
2. Huang Y, Cao D, Chen Z, et al. Red and processed meat consumption and cancer outcomes: Umbrella review. Food Chem 2021;356:129697.
3. Kazemi A, Barati-Boldaji R, Soltani S, et al. Intake of Various Food Groups and Risk of Breast Cancer: A Systematic Review and Dose-Response Meta-Analysis of Prospective Studies. Adv Nutr 2021;12:809-49.
4. Lo JJ, Park YM, Sinha R, Sandler DP. Association between meat consumption and risk of breast cancer: Findings from the Sister Study. Int J Cancer 2020;146:2156-65.
5. Wang D, Dubois RN. Prostaglandins and cancer. Gut 2006;55:115-22.
6. Thomson CA, Giuliano AR, Shaw JW, et al. Diet and biomarkers of oxidative damage in women previously treated for breast cancer. Nutr Cancer 2005;51:146-54.
7. van Loon LJ, Kruijshoop M, Menheere PP, Wagenmakers AJ, Saris WH, Keizer HA. Amino acid ingestion strongly enhances insulin secretion in patients with long-term type 2 diabetes. Diabetes Care 2003;26:625-30.
8. Gunter MJ, Hoover DR, Yu H, et al. Insulin, insulin-like growth factor-I, and risk of breast cancer in postmenopausal women. J Natl Cancer Inst 2009;101:48-60.
9. Snyderwine EG, Venugopal M, Yu M. Mammary gland carcinogenesis by food-derived heterocyclic amines and studies on the mechanisms of carcinogenesis of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). Mutat Res 2002;506-507:145-52.
10. Zheng W, Gustafson DR, Sinha R, et al. Well-done meat intake and the risk of breast cancer. J Natl Cancer Inst 1998;90:1724-9.

Consume two servings of vegetables at both lunch and dinner. As often as possible, include vegetables dark in color and from the cruciferous family: broccoli, Brussels sprouts, cabbage, cauliflower, kale, etc. Vegetables that are both dark and cruciferous contain compounds that can lower your risk of cancer. One serving equals ½ cup of vegetables (which is quite small), or one cup of greens. 

Studies that look at vegetable and fruit intake and how they might relate to breast cancer risk suggest that sufficient vegetable consumption is more likely to decrease breast cancer risk than fruit consumption.^1,2 Studies looking at specific vegetables indicate that greater benefits are found from leafy greens³, vegetables with deep yellow and/ or orange color 2, and those in the cruciferous family.^2,3

Plant products’ health benefits are derived from phytonutrients, components that protect the plant from the environment in which it lives. There tends to be more phytonutrients on the outside of a plant product, meaning the amount is higher the longer the vegetable or fruit is on the plant. Local and seasonal produce has a higher content of phytonutrients compared with produce shipped to the store. Local produce that is grown in green houses or hydroponically (grown in water and without soil) is becoming more common and leads to more phytonutrient-rich produce being available year-round as the produce is kept on the plant longer.  

When you do not have fresh produce available, frozen and canned produce is actually healthier. Compared to traditional retail-fresh produce which is not locally grown, frozen and canned produce have the same vitamin mineral content but have been shown to be higher in phytonutrients.^4,5 

Frozen and canned vegetables:

• Come ready to use
• Are cleaner than fresh vegetables
• Can be purchased on sale and stored

In humans, phytonutrients have been shown to have some amazing health benefits, explaining why people who eat a plant-rich diet tend to be healthier than those who do not. One of the families of phytonutrients is carotenoids, which give color to plant foods – red, yellow, and orange – and the darker the color, the more carotenoid. A sufficient amount of certain carotenoids in the blood has been shown to decrease oxidation and to help fight cancer. A plant product with a dark green color is the chlorophyll in the plant that is covering up one or more of the carotenoids. 

When we eat plant products that contain carotenoids, they are absorbed in the small intestine with any fat present — to make sure you get enough carotenoids into your blood, you need to eat some dietary fat at the same time. 6 Studies looking at the absorption of carotenoids show that cooking vegetables into fat will produce even more carotenoids being absorbed than just adding fat.⁷ The healthiest fat, extra virgin olive oil, is a great choice for preparing vegetables and improves the taste.

Cruciferous vegetables contain the phytonutrient family glucosinolates. Glucosinolates are water soluble, so they are lost when the vegetable is prepared with water. Steaming may preserve them, but they are fully retained if stir fried in fat.⁸ It is not yet known if they are absorbed with the fat like the carotenoids.

If you are not doing so already, start to eat vegetables daily. Include a variety and cook them into olive oil whenever you can. 

References

1. Farvid MS, Barnett JB, Spence ND. Fruit and vegetable consumption and incident breast cancer: a systematic review and meta-analysis of prospective studies. Br J Cancer 2021;125:284-98.
2. Farvid MS, Chen WY, Rosner BA, Tamimi RM, Willett WC, Eliassen AH. Fruit and vegetable consumption and breast cancer incidence: Repeated measures over 30 years of follow-up. Int J Cancer 2019;144:1496-510.
3. Farvid MS, Holmes MD, Chen WY, et al. Postdiagnostic Fruit and Vegetable Consumption and Breast Cancer Survival: Prospective Analyses in the Nurses' Health Studies. Cancer Res 2020;80:5134-43.
4. Rickman JC BC, Barrett DM. Nutritional comparison of fresh, frozen, and canned fruits and vegetables II. Vitamin A and carotenoids, vitamin C, minerals and fiber. Journal of the Science of Food and Agriculture 2007;87:1185-96.
5. Rickman JC BD, Bruhn CM. Nutritional comparison of fresh, frozen and canned fruits and vegetables.  Part 1. Vitamins C and B and phenolic compounds. Journal of the Science of Food and Agriculture 2007;87:930-44.
6. Brown MJ, Ferruzzi MG, Nguyen ML, et al. Carotenoid bioavailability is higher from salads ingested with full-fat than with fat-reduced salad dressings as measured with electrochemical detection. Am J Clin Nutr 2004;80:396-403.
7. Fielding JM, Rowley KG, Cooper P, K OD. Increases in plasma lycopene concentration after consumption of tomatoes cooked with olive oil. Asia Pac J Clin Nutr 2005;14:131-6.
8. Oliviero T, Verkerk R, Dekker M. Isothiocyanates from Brassica Vegetables-Effects of Processing, Cooking, Mastication, and Digestion. Mol Nutr Food Res 2018;62:e1701069.

Add extra virgin olive oil to your meals every day. Extra virgin olive oil is a plant food that provides a range of health benefits, including reduction of blood glucose, blood pressure, and oxidation and inflammation. Studies of women raised on diets that include extra virgin olive oil show that they are less likely to have breast cancer. Please read labels, as there are no health benefits attached to oil that is just labeled “olive oil.” 

Extra virgin olive oil refers to the oil that is closest to the olive, or the “juice.” Chemical and sensory (taste and smell) tests can determine if an olive oil is extra virgin. The benefits are derived from the phenols (which are like phytonutrients) in the olive oil — the higher the phenol content, the greater the health benefits. The phenol content of the oil is highest when it is first made, so it is best to use olive oil that is closest to the production date. The benefits are not from the monounsaturated fat content, and aren’t found in canola oil or other vegetable oils higher in monounsaturated fat.

Studies show that starting at two tablespoons a day of extra virgin olive oil can:

• Decrease oxidation in the body ^1,2 
• Make insulin work better ^3-5 
• Lower blood glucose ^3,6-8
• Decrease inflammation ^9-11  
• Decrease the risk of breast and other cancers

Studies looking at women in the Mediterranean region indicate that using extra virgin olive oil can decrease breast cancer risk. A study published in 1994 of women in Spain showed that while there was no relationship of total fat in the diet to breast cancer, women who reported using more extra virgin olive oil daily had a lower risk of breast cancer compared to those using less extra virgin olive oil. ¹² A study of Greek women published in 1995 found that women who used extra virgin olive oil more than once per day had a 25 percent lower risk of breast cancer compared to those who used it just once per day. ¹³ A more recent study from Spain of women over 60 years old and overweight when they entered the study comparing four tablespoons of extra virgin olive oil per day to daily nuts or a low fat diet showed that breast cancer risk was significantly reduced only in the group that used extra virgin olive oil daily. ¹⁴

The healthiest way to include extra virgin olive oil in your diet is to use it to cook vegetables. Luckily, including extra virgin olive oil often means that you will eat more vegetables. ^15,16 A study that compared cooking vegetables in water; cooking them water with some extra virgin olive oil; or sautéing or frying in extra virgin olive oil showed that extra virgin olive oil preparation was healthiest. This method preserved the vegetables’ phenols, and the phenols in the olive oil went into the cooked vegetables. ¹⁷ Carotenoids, which provide deep color to vegetables, also need fat to be absorbed, ¹⁸ so using extra virgin olive oil to prepare deep color vegetables will help ensure you are getting the components in deep colored vegetables that will fight cancer.

Extra virgin olive oil can be used for cooking – it is a myth that it cannot. Studies done years ago assessing cooking with extra virgin olive oil used excessive cooking temperatures and cooking times that were not comparable to home cooking. ¹⁹ A more recent study published in 2018 showed that olive oil, using a more reasonable time and temperature, is the safest oil to cook with and produces the smallest amount of polar compounds. ²⁰ Interestingly, the study showed that the least healthy oil to cook with is canola oil, which produces polar compounds in amounts greater than what is considered safe for humans.

The health benefits of extra virgin olive oil are best preserved by following some simple steps. The phenols in extra virgin olive oil are damaged by light, heat, and oxygen, with oxygen being the most damaging. ²¹ You should always keep extra virgin olive oil in a covered container and replace the cover as quickly as you can when you are using it. When cooking with extra virgin olive oil you should not leave it in a pan exposed to the air – either cover the pan or stir whatever food into the oil as soon as you can. Air will replace oil in the bottle as you use it, so try to buy bottles of extra virgin olive oil in a size that will allow you to use all the oil within four and, at most, six weeks.

As of this writing (October 2021), the labeling for what qualifies as “extra virgin olive oil” varies throughout the world and some standards unfortunately don’t actually ensure the oil is extra virgin. The California Olive Oil Council website lists their members, producers of olive oils you can trust to be extra virgin. 

References

1. Covas MI, Nyyssonen K, Poulsen HE, et al. The effect of polyphenols in olive oil on heart disease risk factors: a randomized trial. Ann Intern Med 2006;145:333-41.
2. Marrugat J, Covas MI, Fito M, et al. Effects of differing phenolic content in dietary olive oils on lipids and LDL oxidation--a randomized controlled trial. Eur J Nutr 2004;43:140-7.
3. Estruch R, Martinez-Gonzalez MA, Corella D, et al. Effects of a Mediterranean-style diet on cardiovascular risk factors: a randomized trial. Ann Intern Med 2006;145:1-11.
4. Flynn MM, Cunningham, J., Renzulli, J., Mega, A. Including extra virgin olive oil may more improve glycemic control despite similar weight loss compared to the diet recommended by the Prostate Cancer Foundation: a randomized, pilot study. Journal of Cancer Therapy 2017;8:880-90.
5. Paniagua JA, de la Sacristana AG, Sanchez E, et al. A MUFA-rich diet improves posprandial glucose, lipid and GLP-1 responses in insulin-resistant subjects. J Am Coll Nutr 2007;26:434-44.
6. Domenech M, Roman P, Lapetra J, et al. Mediterranean diet reduces 24-hour ambulatory blood pressure, blood glucose, and lipids: one-year randomized, clinical trial. Hypertension 2014;64:69-76.
7. Madigan C, Ryan M, Owens D, Collins P, Tomkin GH. Dietary unsaturated fatty acids in type 2 diabetes: higher levels of postprandial lipoprotein on a linoleic acid-rich sunflower oil diet compared with an oleic acid-rich olive oil diet. Diabetes Care 2000;23:1472-7.
8. Ryan M, McInerney D, Owens D, Collins P, Johnson A, Tomkin GH. Diabetes and the Mediterranean diet: a beneficial effect of oleic acid on insulin sensitivity, adipocyte glucose transport and endothelium-dependent vasoreactivity. Qjm 2000;93:85-91.
9. Barcelo F, Perona JS, Prades J, et al. Mediterranean-style diet effect on the structural properties of the erythrocyte cell membrane of hypertensive patients: the Prevencion con Dieta Mediterranea Study. Hypertension 2009;54:1143-50.
10. Moreno-Luna R, Munoz-Hernandez R, Miranda ML, et al. Olive oil polyphenols decrease blood pressure and improve endothelial function in young women with mild hypertension. Am J Hypertens 2012;25:1299-304.
11. Schwingshackl L, Christoph M, Hoffmann G. Effects of Olive Oil on Markers of Inflammation and Endothelial Function-A Systematic Review and Meta-Analysis. Nutrients 2015;7:7651-75.
12. Martin-Moreno JM, Willett WC, Gorgojo L, et al. Dietary fat, olive oil intake and breast cancer risk. Int J Cancer 1994;58:774-80.
13. Trichopoulou A, Katsouyanni K, Stuver S, et al. Consumption of olive oil and specific food groups in relation to breast cancer risk in Greece. J Natl Cancer Inst 1995;87:110-6.
14. Toledo E, Salas-Salvado J, Donat-Vargas C, et al. Mediterranean Diet and Invasive Breast Cancer Risk Among Women at High Cardiovascular Risk in the PREDIMED Trial: A Randomized Clinical Trial. JAMA Intern Med 2015;175:1752-60.
15. Flynn M, Schiff, AR. A Six-week Cooking Program of Plant-based Recipes Improves Food Security, Body Weight, and Food Purchases for Food Pantry Clients. Journal of Hunger & Environmental Nutrition 2013;1.
16. Flynn MM, Reinert SE. Comparing an olive oil-enriched diet to a standard lower-fat diet for weight loss in breast cancer survivors: a pilot study. J Women's Health (Larchmt) 2010;19:1155-61.
17. Ramirez-Anaya Jdel P, Samaniego-Sanchez C, Castaneda-Saucedo MC, Villalon-Mir M, de la Serrana HL. Phenols and the antioxidant capacity of Mediterranean vegetables prepared with extra virgin olive oil using different domestic cooking techniques. Food Chem 2015;188:430-8.
18. Brown MJ, Ferruzzi MG, Nguyen ML, et al. Carotenoid bioavailability is higher from salads ingested with full-fat than with fat-reduced salad dressings as measured with electrochemical detection. Am J Clin Nutr 2004;80:396-403.
19. Santos C.S.P.C.R. CSC, Casal S. Effect of cooking on olive oil quality attributes. Food Research International 2013;54:2016-24.
20. De Alzaa G RL. Evaluation of chemical and physical changes in different commercial oils during heating. ACTA Scientific Nutritional Health 2018;2:2-11.
21. Li X BG, Connell KN, Ngai C, Pham QAT, Wang S, Flynn M, Ravetti L, Guillaume C, Wang S. Changes in chemical compositions of olive oil in home cooking conditions. Journal of Food Chemistry and Nutrition 2016;4:7-15.

Limit or avoid vegetable seed oils such as corn, grape seed, safflower, and soybean and the foods that contain them (margarine, mayonnaise, and commercial salad dressing). The main type of fat in these oils will oxidize or break down in your body, leading to greater risk of disease. 

Vegetable seed oils are high in what are called polyunsaturated fats, with two or more double bonds (don’t worry about the chemistry). Because of the double bonds, these oils can easily break down or oxidize. We cannot stop oxidation in the body because we breathe in oxygen all day long. However, uncontrolled oxidation is related to an increase in oxidation and inflammation, which can increase the risk of several chronic diseases including cancer. Limiting or, even better, eliminating polyunsaturated fats in your diet you can greatly decrease the oxidation in your body. 

The fat we eat becomes part of any tissue in our body after being absorbed from the intestinal tract. Tissue that contains fat includes all cell membranes, fat tissue (adipose tissue), and the lipoproteins (LDL, HDL). We do not make polyunsaturated fats, so any amount of polyunsaturated fat found in a person is from what they have eaten over time. A study showed women with breast cancer had higher fat oxidation in their breast tissue, indicating polyunsaturated fat, compared to women without breast cancer. ¹  Another study found that postmenopausal women who consumed diets higher in polyunsaturated fats were at higher risk of breast cancer. ²

Try to avoid vegetable seed oils and their products. You can easily substitute extra virgin olive oil for vegetable seed oils for both cooking and baking. 

References

1. Kumaraguruparan R, Subapriya R, Viswanathan P, Nagini S. Tissue lipid peroxidation and antioxidant status in patients with adenocarcinoma of the breast. Clin Chim Acta 2002;325:165-70.
2. Wirfalt E, Mattisson I, Gullberg B, Johansson U, Olsson H, Berglund G. Postmenopausal breast cancer is associated with high intakes of omega6 fatty acids (Sweden). Cancer Causes Control 2002;13:883-93.

Eat three meals a day as often as you can and avoid snacking. Our bodies are more likely to store calories when we eat small amounts, so compared to meals, snacking can lead to more weight gain. 

Eating three meals a day is preferable to snacking throughout the day for a couple of reasons. When we metabolize food, we use some energy or calories to digest and absorb it. This is called the Thermic Effect of Food (TEF) and is noticeable after eating a meal when in a warm environment (you could start to sweat) or in a cold environment (you get warm). TEF is more efficient with small amounts of food, meaning we are more able to store the calories and would store them as fat. Snacking is good for small children, older or sick people, or anyone who needs to gain weight. For the rest of us, it can lead to weight gain. 

The concept of snacking is relatively new and was not common among adults prior to about 1980. But since that time, snacking has increased while time between eating occasions has decreased. ¹ At least some of the increase in snacking is related to the increase in people eating low-fat meals/diets. When you eat a meal with insufficient fat, you are not satisfied and may eat a lot of extra calories until your hunger subsides. 

If you know you can eat in a couple hours, i.e., a snack, it can make it easier to deal with the hunger. As we all know, low-fat diets have failed miserably in lowering body weight. A comparison of people who eat at most three times a day (or those who eat meals) with those who eat five or more times a day (snacking) showed that snacking can increase the risk of being overweight by approximately 50 percent. ²

The other reason meals are better than snacks for weight maintenance is that a meal results in an increase in nutrients (glucose, fatty acids, and amino acids) in the insulin secreted into the blood. Meaning, when there is insulin in the blood we are storing nutrients. When insulin is low, several hours after you eat (the actual time is dependent on how much and what you ate), you are able to release fat for energy to run your body. This is what happens if you are feeling a bit hungry and you start to move — in about 20 minutes, you will notice that your hunger is gone. This is because your fat cells are releasing fat into the blood to fuel your energy, and the blood with the fat goes through your brain, shutting off the hunger signals. 

Your brain does not know if the fat in the blood is from food you ate or from fat you have stored on your body, and it doesn’t matter. The brain just realizes there are nutrients available, so it turns off the hunger signals. Snacking all day is counterproductive for weight loss and appropriate weight management — if you are eating all day, you are never able to release stored fat. 

References

1. Popkin BM, Duffey KJ. Does hunger and satiety drive eating anymore? Increasing eating occasions and decreasing time between eating occasions in the United States. Am J Clin Nutr. 2010;91(5):1342-1347.
2. Murakami K, Livingstone MB. Eating Frequency Is Positively Associated with Overweight and Central Obesity in U.S. Adults. J Nutr. 2015;145(12):2715-2724.

Try not to “drink” your calories. Some studies have shown that we are more likely to gain weight when we drink our calories compared to when we eat them. ¹ Excess calories can come from soda, lemonade, juice, and any sweetened beverage. Healthier alternatives include water or seltzer, or unsweetened coffee, tea, and herbal teas (hot or iced).

Limit the amount of fluid you drink containing calories, including milk and juice. Drinking a glass of fruit juice could add more weight over time than eating the fruit itself. If you are someone who likes to consume “smoothies” make sure you know how much fruit you are using, as the calories can quickly add up. Each piece of fruit would have at least 100 calories (often more if it’s a large piece), so keep track of how much fruit you are adding to the blender. 

If you add sugar to your coffee or tea, consider adding less. At the very least, make sure you are adding it yourself and not having it added for you. 

Reference

1. Almiron-Roig E, Chen Y, Drewnowski A. Liquid calories and the failure of satiety: how good is the evidence? Obes Rev 2003;4:201-12.

Limit your eating out. The more you dine out, the more difficult it is to control your intake of foods which could contribute to being overweight.  If you do eat out, follow the guidance of a plant-based, Mediterranean diet. 

This includes dining out for breakfast and lunch. We often don’t think of cafeteria food at work as “dining out,” but it counts. What is served for a portion of food in a restaurant is most often more than what you would eat at home. Also, the same amount of food is served to everyone in a restaurant, regardless of their size. It can help to plan in advance to take a portion or even half of a restaurant meal home. You will be eating less and have a future meal ready to eat.

If you work outside the home, make an effort to bring your lunch with you to work as often as you can, or at least three days out of the work week. This involves “meal planning,” which was very common for years but seems to have fallen out of favor. Meal planning simply means you have a least a rough idea of what your meals will be for a period of time. It helps to make sure that you have the foods you will need while grocery shopping.

There are many simple meals you could make that likely take less time than it would to order, pick up, and bring back a meal — and definitely cost less than dining out. If you currently eat out more than one meal per week, start with just making a few meals a week and time how long it takes you to make the meal. You may be surprised at how quick it can be!

If you drink alcohol, it’s best to stick to no more than one drink per day. The relationship of alcohol consumption to breast cancer risk is far from clear — while the media focuses on studies that show alcohol consumption increases risk, there are many studies that show no increase, one that is very small, or even a benefit:

• A study of Swedish women found no increase in breast cancer risk for up to 30 grams (two drinks) a day.¹  
• A study of premenopausal women found no increase in breast cancer risk for up to 27 drinks a week. ²  
• A study of French women found that compared to women who did not drink, those who drank approximately one glass of wine per day had a much lower risk of breast cancer. ³  
• A study of women diagnosed with breast cancer before the age of 45 who consumed seven drinks a week had a 40 percent lower risk of death compared to women who did not drink. ⁴ 
• A U.S. study including over 22,000 women that looked at alcohol consumption before and after diagnosis show increase in breast cancer risk for those who drank before diagnosis and no association with survival for those who consumed alcohol after diagnosis. ⁵ In addition, the study found moderate consumption (3-6 drinks per week) both before and after diagnosis actually improved overall survival rates. 

The mixed results are due to a number of factors. A standard drink of alcohol contains approximately 14 grams of alcohol and is equal to 12 fluid oz. of beer, 5 fluid oz. of wine, and 1.5 fluid oz. of spirits. Studies often report drinks per week — while this would be easy to capture with beer (one could count the number of bottles), glasses of wine are not standard and studies do not report how the women were told to assess their wine intake. If you were making the drink at home you would know how much alcohol was used but if the consumption was outside the home, one would have no idea how much alcohol was in the drink. 

While there are standard drink sizes, studies often report alcohol data using ten-gram increments. This would mean if the study assessed intake as up to ten grams, it would represent less alcohol than a standard drink, and 10-20 grams would be a bit more, making it difficult to assess the relationship of risk to the number of standard drinks. 

Also, reporting “drinks per week” could introduce additional error. While seven drinks per week in Europe is likely one per day, U.S. drinking often occurs just on the weekend, meaning three or four drinks on Friday and Saturday. Assessing the pattern of drinking is very important, as there is evidence that indicates that when alcohol consumption is just one to three days in a week there is more likely to be an increase breast cancer risk compared to the same amount of alcohol spread over four to seven days. ⁶ 

Other aspects of one’s diet are typically not included in the studies, which could be important. For example, a participant who reports no alcohol consumption could be someone whose diet contains frequent beef consumption and limited plant products, while someone who reports daily wine could be vegan with high consumption of plant products and no beef consumed. The health impacts of eating frequent beef or frequent plant products would contribute opposite health impacts and may override any effect of alcohol. Many studies divide the participants by body weight and measure difference for overweight versus normal weight, which would be useful. Some studies indicate only specific types of breast cancer are related to benefit or harm from alcohol consumption. 

Other studies suggest the relationship may depend on menopausal status. Most studies only report “alcohol” intake and do not look at the risk by alcohol type, which could make a difference. For example, a study published in 1994 of Greek women found that while beer consumption could increase breast cancer risk more than 30 percent, there was no increase in risk for wine or spirits consumption. ⁷ In another study of more than 4,000 women who had been diagnosed with breast cancer, wine consumption of seven or more drinks a week was inversely related to breast cancer mortality, meaning higher wine consumption meant a lower risk of death from breast cancer. ⁸

As the studies do not consistently indicate there is a risk (or benefit) to alcohol consumption and breast cancer risk, a decision was made to use the current standard recommendation in the U.S. of one drink per day. However, keep in mind that eating an overall healthy diet, which means multiple daily servings of vegetables and some fruit, seems to be more important than whether you drink alcohol. 

References

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