Quality or Quantity of Proteins in the Diet for CKD Patients: Does “Junk Food” Make a Difference? Lessons from a High-Risk Pregnancy

Abstract

<b><i>Background:</i></b> How to manage patients with severe kidney disease in pregnancy is still a matter of discussion, and deciding if and when to start dialysis is based on the specialist’s experience and dialysis availability. The effect of toxic substances usually cleared by the kidney may be more severe and readily evident. The review, and related case, underlines the importance of considering the presence of additives in food in delicate conditions, such as CKD pregnancy. <b><i>The Case:</i></b> A 39-year-old indigenous woman from a low-resourced area in Mexico was referred to the obstetric nephrology at 25 gestational weeks because of serum creatinine at 3.6 mg/dL, hypertension on low-dose alpha-methyl-dopa, and nephrotic-range proteinuria. Kidney ultrasounds showed small poorly differentiated kidneys; foetal ultrasounds detected a female foetus, normal for gestational age. The patient’s baseline protein intake, which was estimated at 1.2–1.3 g/kg/day, was mostly of animal-origin (>70%) poor-quality food (“junk food”). In the proposed diet, protein intake was only slightly reduced (1.0–1.2 g/kg/day), but the source of proteins was changed (only 30% of animal origin) with attention to food quality. A remarkable decrease in BUN was observed, in concomitance with adequate dietary follow-up, with rapid rise of BUN when the patient switched temporarily back to previous habits. A healthy female baby weighing 2,460 g (11th centile for gestational age) was delivered at 37 gestational weeks. <b><i>Discussion and Literature Review:</i></b> While data on patients with chronic kidney disease are scant, the long list of contaminants present in food, especially if of low quality, should lead us to reflect on their potential negative effect on kidney function and make us realize that eating healthy, unprocessed “organic” food should be encouraged, in delicate conditions such as pregnancy and breastfeeding and for young children, in particular when kidney function is failing. The case herein described gave us the opportunity to reflect on the importance of diet quality and on the potential risks linked to food additives, many of which, including phosphates and potassium, are not declared on food labels, while others, including dyes, antioxidants, thickeners, emulsifiers, and preservatives, are qualitatively, but not quantitatively, reported.

Plant-Based Diets Improve Maternal–Fetal Outcomes in CKD Pregnancies

“…While previous studies already suggested that such a nutritional approach is safe and is associated with better pregnancy outcomes, the limits of the previous analyses were linked to the small number of cases studied and the lack of a well-matched control group [ 29 , 30 , 31 , 32 , 33 ]. This is the first time that we are reporting the results of a study involving a larger group of on-diet patients, compared with a control group that was propensity-matched for the two main elements considered for diet prescription (CKD stage and proteinuria).…”

“…Based on the kidney function, proteinuria levels, and the individual patient’s needs and preferences, we allowed 1–3 unrestricted meals per week (without protein restriction but limited in unsaturated fats and short-chain sugars, as indicated in pregnancy). To facilitate compliance with a plant-based diet without the need to eat pulses and cereals at each meal, as it is necessary to avoid deficits of specific aminoacids (in particular lysine), in most cases, supplementation of alpha-keto analogues and aminoacids (Alpha-Kappa or Ketosteril) was added (1 tablet per each 8–10 kg of pregestation body weight) [ 28 , 29 , 30 , 31 , 32 , 33 ]. This choice was indeed made to remain “on the safe side” and to avoid the risk of deficits of specific aminoacids in patients who were not used to a plant-based regiment before pregnancy.…”

“…In this context, our team and a few others tried to counterbalance pregnancy-induced hyperfiltration and reduce proteinuria by employing plant-based diets with moderately reduced protein intake during pregnancy [ 29 , 30 , 31 , 32 , 33 ].…”

Supplemented Low-Protein Diet May Delay the Need for Preemptive Kidney Transplantation: A Nationwide Population-Based Cohort Study

“…The importance of supplemented low-protein diets has been recently underlined in the new KDOQI guidelines, principally for their advantage of allowing a longer follow-up in the pre-dialysis phase [ 35 ]. High-quality diets with appropriate restriction of protein have been regarded as a crucial treatment in CKD population [ 36 ]. However, to the best of our knowledge, only one small study had focused on the advantage of this policy while waiting for pancreas-kidney transplantation, and no study had been performed to analyze the effect of this dietary approach on delaying time to transplantation in patients scheduled for living-donor kidney transplantation [ 21 ].…”

Junk food-induced obesity- a growing threat to youngsters during the pandemic

“… Type of Junk Food Components Impact on health Fish sauce, Soy sauce ( Olney et al, 1972 ; Lemkey-Johnston and Reynolds, 1974 ; Holick, 2003 ) Monosodium Glutamate Overweight, Brain lesions, obesity, diabetes, neurotoxic effects, endocrine disorders Sweetened Soda, soft drinks ( DeChristopher et al, 2020 ; Chapman et al, 2020 ) High Fructose Corn Syrup Weight gain and Diabetes, Hypertension, atherosclerosis, coronary heart disease, vascular resistance in the kidneys Margarine, French fries, Dough nut, Pastry, Ice-cream ( Islam et al, 2019 ; Zhu et al, 2019 ) Trans Fat Increase in Inflammatory markers (Heart Risk), T2DM, cancer and diabetes, cardiovascular disease Buns, Bagels, flour bleaching agent and a dough conditioner. ( Kim et al, 2004 ; Ye et al, 2011 ) Azodicarbonamide Asthma, carcinogenicity Frenchfry cardboard sleeves, Burger and sandwich wrappers, Bread wrappers, containing Fluorine ( Hurley et al, 2018 ; Anderko and Pennea, 2020 ) Per/poly fluoroalkyl substances (PFAS) Breast cancer, Fertility, Weakened Immune system, Soda, Flavoured water, processed cheese, chicken nuggets ( Orozco-Guillien et al, 2021 ) Phosphate additives Kidney disease, Bone problem Mayonnaise, Roasted pork ( Ham et al, 2019 ; Yang et al, 2017 ) Propyl gallate Reproductive toxicant, testicular toxicity, abnormal implantation and placental development. Burger packaging ( Li et al, 2021 ) Phthalates Induce Reproductive toxicity towards the development of gonads and reproductive capability of environmental organisms.…”