Soda and Breast Cancer: What You Need to Know

People undergoing breast cancer treatment are generally advised to limit or avoid soda (soft drinks), especially sugar-sweetened and carbonated varieties. This recommendation helps manage side effects and supports overall health during and after treatment. ^[1] Soda and other carbonated drinks can aggravate symptoms like reflux and may add excess sugar and empty calories, which are best minimized. ^{[2] [3]}

Why soda is discouraged

• Added sugars and calories: Many sodas are high in added sugar, which can contribute to weight gain and metabolic issues; it’s considered wise to limit sugars from drinks and total calories. ^{[4] [3]}
• Carbonation and reflux: Fizzy drinks can worsen heartburn and reflux, which are common during treatment; avoiding carbonated beverages can help. ^[2]
• Fatigue and dehydration: Sweetened beverages can be dehydrating or exacerbate symptoms, so it’s better not to drink many sweetened soft drinks and juices. ^{[1] [5]}

Safety vs. moderation

Soda is not “forbidden,” but limiting or avoiding soft drinks especially sugar-sweetened and carbonated aligns with practical nutrition guidance for breast cancer care. ^{[1] [2]} If you choose to have soda occasionally, keeping portions small and choosing options with less sugar can reduce potential downsides. ^{[3] [6]}

Potential effects on outcomes

• Cancer risk and recurrence (observational data): Higher intake of sugar-sweetened beverages has been linked with modestly increased breast cancer risk in some observational analyses, suggesting prudence in limiting these drinks. [PM16] While causation isn’t proven, several reviews recommend limiting sweet beverages as a precaution. [PM25]
• Post‑diagnosis survival: Postdiagnosis sugar‑sweetened beverage consumption has been studied in relation to mortality among women with breast cancer; results support an approach of minimizing sugary drinks after diagnosis. [PM15]
• Artificially sweetened beverages: Large cohort and analytic studies show mixed findings, with no consistent strong link to breast cancer risk; however, focusing on overall diet quality and minimizing sweet beverages remains sensible. [PM14] [PM27]

Practical drink choices

• Better options: Water, unsweetened tea, diluted electrolyte drinks (as advised for specific symptoms), and broths can be helpful during treatment. ^[7]
• Limit juice: Keep 100% fruit juice to about 8 ounces (1 cup) per day to avoid excess sugar. ^[8]
• Caffeine: Most people can have moderate amounts (1–2 cups/day) of coffee or caffeinated tea; avoid sweetened energy drinks and alcohol. ^[9]
• Green tea: Limit to no more than 16 ounces (2 cups) daily. ^[10]

Managing common symptoms

• Reflux/heartburn: Avoid acidic foods and carbonated drinks; eat smaller meals and remain upright after eating to reduce symptoms. ^[2]
• Hot flashes: Coffee, soda, and energy drinks may worsen hot flashes in some individuals; reducing these triggers can help. ^[11]
• Nausea/vomiting: After vomiting stops, choose drinks with electrolytes, ice pops, and broths, and reintroduce small amounts of solids gradually. ^[7]

Sugar limits and label tips

• Daily added sugar: A practical benchmark is to keep added sugar to no more than about 25 grams (6 teaspoons) per day for a 2,000‑calorie diet. ^[12]
• Label reading: Check grams and % Daily Value for added sugars, and save foods or drinks with more than 15 grams of sugar per serving for special occasions. ^{[12] [13]}
• Sugar is sugar: Whether raw, brown, white, organic, or powdered minimizing added sugar across sources is helpful. ^[13]

Bottom line

• It’s generally advisable to limit or avoid soda particularly sugary and carbonated types during breast cancer treatment to manage symptoms and support overall health. ^{[1] [2]}
• If consumed, keep it occasional and small, and consider alternatives like water or unsweetened beverages to meet hydration needs without excess sugar. ^{[3] [6]}