Contaminated Protein Bars?

Written by Erika Behrmann RD, CSSD, CDCES, LDN

Nutrition bars have long been favored as convenient and portable sources of energy and nutrients for those on the go. However, recent scrutiny has revealed inconsistencies between what these bars claim to offer and their actual content. Tests conducted by ConsumerLab (CL) over the years have shown that while some bars uphold their nutrient claims, discrepancies in carbohydrates, fats, and other elements continue to surface, raising questions about label accuracy and consumer trust.

In 2001, ConsumerLab (CL) found many to be mislabeled, often with undeclared carbohydrates, leading to FDA warnings. By 2005, most bars met nutrient claims, and by 2008 all tested bars complied. However, issues resurfaced: two bars in 2013 had higher cholesterol and saturated fats than claimed. In 2019, three bars failed for inaccuracies in carbohydrates, fats, cholesterol, or fiber. Regular testing by federal or state agencies does not occur, but CL's independent testing aims to fill this gap. The analysis includes various nutrients and potential contaminants like heavy metals. Recently, tests revealed that while protein and fiber claims are generally accurate, some bars exceed claimed fat and carbohydrate levels, or sugar alcohols, leading to non-approval. High cost did not align with higher quality.

ConsumerLab (CL) independently purchased and tested popular nutrition bars from brands like Aloha, Barebells, Clif Bar, GoMacro, David, IQ Bar, Kind, Larabar, Kirkland (Costco), Perfect Bar, Pure Protein, Quest, and RxBar. The results showed that each nutrition bar contained its protein and fiber content claims, and upheld gluten free certifications. However, several products failed to live up to claims regarding fats, with one bar containing 8 additional grams of mostly saturated fat. One with 7 extra grams of carbohydrates, and sugar alcohols with one having more than 75% than listed. These products were NOT APPROVED.

Heavy Metals - Generally not a problem, but a small concern with lead. CL found a small amount of lead in each product, generally ranging from 0.17 mcg to 0.75 mcg per bar, with one product having somewhat more (1.1 mcg per bar in Pure Protein - Chocolate Deluxe). These amounts (shown in the 6th column of the Results table) pose little risk at one bar per day, although some exceed the strict California Prop 65 level of 0.5 mcg per daily serving, above which a warning is required regarding reproductive harm if used on a chronic basis. Child-bearing women, as well as young children, may want to limit consumption of products that exceed this level. Amounts of arsenic, cadmium and mercury did not exceed established risk levels.

Top picks based on quality, taste, and value include:

Energy bar:

GoMacro Peanut Butter Chocolate Chip

  • Runner up lower cost alternative with more fiber - Clif Bar Crunchy Peanut Butter

  • Runner up for “short and long term energy” - Perfect Bar Peanut Butter

High Protein Bar/High Protein Nut Bar:

RX Bar Chocolate Sea Salt

  • Runner up - Pure Protein Deluxe Chocolate

Fruit & Nut Bars:

Kirkland Signature Nut Bars with Cocoa Drizzle and Sea Salt

  • Runner up, fruitier and more nuts - Larabar Peanut Butter Chocolate Chip

All Approved bars include:

Clif Bar Crunchy Peanut Butter

Aloha Peanut Butter Chocolate Chip

Barebells Protein Bar Cookies & Cream

Pure Protein Chocolate Deluxe

Quest Hero Protein Bar Crispy Chocolate Peanut Butter Flavor

Perfect Bar Peanut Butter

KIND Caramel Almond Sea Salt

KIND Dark Chocolate Nuts & Sea Salt with Almonds & Peanuts

Kirkland  Signature (Costco) Nut Bars with Cocoa Drizzle & Sea Salt

Larabar Peanut Butter Chocolate Chip

GoMacro Peanut Butter Chocolate Chip

RX Bar Chocolate Sea Salt

Not Approved Bars:

David Fudge Brownie Flavored Bar (for having more calories 229 vs 150, total fat 9.7 vs 2g, and saturated fat 8.3 vs 1.5g) than listed on the label.

IQ Bar Chocolate Sea Salt  (for having more carbs 17.1g vs 10g and sugars 3.6g vs 1g )than listed.

Kirkland Signature (Costco) Protein Bar Chocolate Chip Cookie Dough (for having more erythritol 3.5 vs 2g) than listed.

Be aware that Nutrition Bars can help provide some of the recommended daily protein (5-6.5 oz equivalents per day) but they are not recommended as a total substitute for food. A downside of many high protein bars is that they tend to be relatively higher in saturated fats, keto bars especially containing coconut or MCT oil. 

Keep in mind that protein and nutrition bars are often ultra processed which means their formulations combine extracts of original foods with additives and industrial ingredients as opposed to whole foods or minimally processed foods. Even people who switch to a diet meeting healthy dietary guidelines have been shown to lose less weight if most of the calories come from foods that are ultra processed rather than minimally processed, with one 8-week study showing only half the amount of weight loss (and less fat loss) with a diet high in ultra processed foods compared to one high in minimally processed foods. 

ConsumerLab's independent testing of prominent nutrition bar brands highlights the gap in quality assurance left by the lack of routine federal testing. While bars such as GoMacro Peanut Butter Chocolate Chip and RX Bar Chocolate Sea Salt are praised for their quality, taste, and value, others like David Fudge Brownie and Kirkland Signature fail due to significant label inaccuracies. The testing suggests that while these bars can contribute to daily protein intake, they should not replace whole foods due to potential high saturated fat content and ultra-processing, which may affect health outcomes like weight management.

Holley Samuel